Unit 2 Qbank, Microbiology

Which of the following is used to classify viruses? i. Nucleic acid ii. Shape iii. Size iv. Host range v. Biochemical tests

(i), (ii), (iii), and (iv)

Cells infected with animal viruses lyse because: - the release of the virions depletes the cell of energy. - the virus releases enzymes that lyse the cell. - functions necessary for cell survival are not carried out and the cell dies. - the virus RNA and cellular protein interact to kill the cell.

*functions necessary for cell survival are not carried out and the cell dies.

Which of the following statements about helminths is FALSE? - Some have male and female reproductive organs in one animal. - They are heterotrophic. - They have eukaryotic cells. - They are multicellular animals. - All are parasites.

- All are parasites. Some are parasites. Helminths are worms, a type of animal.

Fungi that are important for fermentation of fruits: - are yeasts. - are facultative anaerobes. - grow well at acid pH. - secrete enzymes that degrade organic molecules. - All of the choices are correct.

- All of the choices are correct

Which of the following statements regarding protozoa is FALSE? - Some protozoa are parasitic. - All protozoa lack mitochondria. - Protozoa are unicellular organisms. - Some protozoa are photosynthetic. - Trichomoniasis is caused by a protozoan.

- All protozoa lack mitochondria.

Yeast infections are caused by: - Saccharomyces cerevisiae. - Candida albicans. - Histoplasma. - Penicillium. - Aspergillus.

- Candida albicans.

Which of the following organisms is photoautotrophic protozoan? - Phytophthora - plasmodial slime mold - cellular slime mold - Euglena - oomycote

- Euglena

Transduction resulting from a packaging error: Transduction resulting from an error in excision of a prophage:

- Generalized Transduction - Specialized Transduction

Which of the statements regarding Naegleria fowleri is FALSE? - Once in a human host, it assumes an amoeboid form. - It is swims though water as a flagellated form. - It causes primary amebic meningoencephalitis (brain eating disease). - It is a small, Gram-negative, flagellated diplococcus. - It forms a cyst under adverse environmental conditions.

- It is a small, Gram-negative, flagellated diplococcus. - an amoeboid Protozoa Naegleria fowleri infects people when water containing the AMOEBA enters the body through the nose. This typically occurs when people go swimming or diving in warm freshwater places, like lakes and rivers. The Naegleria fowleri ameba then travels up the nose to the brain where it destroys the brain tissue. - can't live in salt or treated water.

You have isolated a bacterium from a contaminated river but you are unable to culture it in the laboratory. Which method could you use to identify the organism? - Gram staining - Biochemical testing - MALDI-TOF mass spectrometry - Nucleic acid amplification tests - Antibiograms

- Nucleic acid amplification tests

Which of the following are characteristics of fungi? -They have a nuclear membrane AND their cell wall contains cellulose. - Their cell wall contains chitin AND they use nutrients from dead or decaying organic matter. - Their cytoplasmic membrane contains ergesterol AND they are always multicellular. - They have a peptidoglycan cell wall AND they may be photosynthetic. - Their cell wall contains cellulose AND they use nutrients from dead or decaying organic matter.

- Their cell wall contains chitin AND they use nutrients from dead or decaying organic matter.

Phage that lyses the bacterial host when completing its life cycle: Phage that is able to incorporate its genome into the host chromosome:

- Virulent Phage -Temperate Phage

The lactobacilli, in their role as normal microbiota of the vagina, help the vagina resist infection by contributing to: - a high vaginal pH. - the neutrality of the vaginal mucus. - food for the resident vaginal microbiota. - fertility of the host. - acidity of the vagina.

- acidity of the vagina

If you had three tubes of flu viruses and you exposed tube 1 to protease, tube 2 to protease and RNase, and tube 3 to protease and DNase, and the contents of tube 2 were be degraded, you would be able to conclude that: a protein virus. an opportunist. resistant to proteases. a DNA virus. an RNA virus.

- an RNA virus RNases cleave RNA molecules

Streptococcus pyogenes would be - beta hemolytic and catalase negative. - beta hemolytic and catalase positive. - alpha hemolytic and catalase negative. - alpha hemolytic and catalase positive.

- beta hemolytic and catalase negative.

A positive (+) strand of RNA: The negative (-) sense strand of RNA:

- can directly act as mRNA - is used to synthesize more (+) strands.

The encysted larva of the beef tapeworm is called a: - metacercaria. - redia. - proglottid. - cercaria. - cysticercus.

- cysticercus.

In conjugation, transformation, or transduction, the recipient bacteria is most likely to accept donor DNA: - from any species of bacteria. - from the same species of bacteria. - from any source AND only through plasmids. - only through plasmids. - from any source.

- from the same species of bacteria.

Ringworm is caused by a(n)? - trematode. - nematode. - fungus. - cestode. - protozoan.

- fungus

Helminthic diseases are usually transmitted to humans by: - aerosols. - vectors. - respiratory route. - genitourinary route. - gastrointestinal route.

- gastrointestinal route.

All of the following are characteristic of the Platyhelminthes EXCEPT that they? - are multicellular animals. - are hermaphroditic. - are dorsoventrally flattened. - can be divided into flukes and tapeworms. - have highly developed digestive and nervous systems.

- have highly developed digestive and nervous systems.

Helicobacter pylori: - causes crown gall in plants. - inhabits the stomach. - has axonemes. - produces luminescence. - inhabits squid ink sacs.

- inhabits the stomach

Giardia and Trichomonas are unusual eukaryotes because they: - are motile. - lack nuclei. - lack mitochondria. - do produce cysts. - do not produce cysts.

- lack mitochondria. Giardiasis is an intestinal infection in humans and animals, caused by a microscopic protozoan parasite Giardia duodenalis (also known as G. intestinalis or G. lamblia). "Giardia is not a "worm", bacteria or virus." Trichomoniasis (or "trich") is a very common sexually transmitted disease (STD). It is caused by infection with a protozoan parasite called Trichomonas vaginalis. Although symptoms of the disease vary, most people who have the parasite cannot tell they are infected.

Algae are important environmentally as: - local contaminants. - major producers of oxygen. - supporting fungal growth. - local flora. - major producers of carbon dioxide.

- major producers of oxygen.

Fungi are classified according to their - mode of locomotion. - this is protozoans - cap color. - morphology. - method of sexual reproduction. - mode of nutrition.

- method of sexual reproduction. - found it. slide 18 - The sexual forms (of reproduction) play an important role in FUNGAL CLASSIFICATION and some are commercially valuable.

The human body only contains bacteria during illness. True or Flase False Viruses, viroids and prions all: - operate intracellularly. - may be considered acellular agents of disease. - contain DNA. - infect only animals. - operate intracellularly AND may be considered acellular agents of disease.

- operate intracellularly AND may be considered acellular agents of disease.

A virion is composed of: - protein, either RNA or DNA, and possibly lipid. - protein and either RNA or DNA, but no lipid. - protein, and possibly lipid. - lipid, protein, and either RNA or DNA. - protein and both RNA and DNA, but no lipid.

- protein, either RNA or DNA, and possibly lipid.

Fungi that are important for fermentation of fruits: - grow well at neutral pH. - are mushrooms. - are obligate aerobes. - secrete degradative enzymes. - All of the choices are correct.

- secrete degradative enzymes.

The genus of bacteria that is able to fix nitrogen and form heterocysts is

-Anabeana

Algae

-May be green, red, or brown. -Lack roots, stems, leaves, and vascular tissues that are found in terrestrial plants. -Some marine produce neurotoxins that can be concentrated in shellfish and pose a risk of paralytic shellfish poisoning to humans who consume the shellfish. -Both asexual and sexual reproduction occurs among the diversity of species. -Most have a plantlike cell wall composed of cellulose.

Protozoa

-Most protozoa are motile via pseudopods, flagella, cilia, or undulating membranes. -Cysts enable parasites to survive during passage from one host to the next. -While living in the gut of their host, intestinal parasites are usually in the trophozoite form. -As a group exhibit both asexual and sexual reproduction.

Helminths

-The major organ system apparent in tapeworm proglottids is the reproductive system. -Some helminth infections involve more than one intermediate host. -Either eggs or larval stages may be infectious, depending on the species. -Parasitic lack a complete digestive system and they absorb nutrients directly through their cuticles. -Humans can serve as either definitive or intermediate hosts of flatworms.

Some fungi reproduce sexually by forming----- which are sexual spores contained within a sac structure.

-ascospores

The properties of a cell that are determined by its DNA composition are its: - nucleoid. - phenotype. - metabolism. - plasmids. - genotype.

-phenotype

Viruses: - probably keep the numbers of bacteria in check. - have no effect on the number of bacteria. - increase the number of bacteria. - are active in passing DNA from one bacterium to another. -probably keep the numbers of bacteria in check AND are active in passing DNA from one bacterium to another

-probably keep the numbers of bacteria in check AND are active in passing DNA from one bacterium to another

Rhizopus stolonifer, the common black bread mold, forms asexual spores called----- which are contained in a sac at the end of aerial hyphae.

-sporangiospores

You are a volunteer for Nurses Without Borders and are being sent to a country in Africa. You are excited, because you will have opportunities to go on safari, but you are also somewhat concerned because you have learned from the CDC website that there is currently cholera in the country to which you are going. Patients with cholera experience vomiting and severe diarrhea, producing several liters of liquid stool in a day. This results in signs of dehydration, including sunken eyes, muscle cramps, and in a few cases, convulsions and death. Cholera is caused by the bacterium Vibrio cholerae. You make a list of questions about V. cholerae that you answer with the help of your nursing school study group. All bacteriophages must be able to: 1. inject their DNA into the host cell 2. cause a genetic change in the host cell 3. kill the host cell 4. replicate in the absence of a host 5. exit a host cell by extrusion 1, 4, and 5 1 only 2 only 1, 2, and 4 1, 2 and 3

1 only

Which are the three ways in which fungi cause illness in humans? 1. Hypersensitivity - person has allergic reaction to fungal components. 2. Intoxication - fungus produces a toxin that is ingested. 3. Immune suppression - fungus destroys all red blood cells. 4. Infection - fungus grows on body as a mycosis. -- 1. 1, 2, and 4 2. 4 only 3. 2, 3, and 4 4. 1, 3, and 4 5. 1, 2, and 3

1. 1, 2, and 4

One of the organisms that may cause red tide is: 1. dinoflagellates. 2. euglenids. 3. diatoms. 4. green algae. 5. brown algae.

1. dinoflagellates.

One of the greatest causes of human deaths through time has been due to: 1.Plasmodium spp. 2.Giardia spp. 3.Escherichia spp. 4.Trypanosoma spp. 5.Histoplasma spp.

1.Plasmodium spp. - causes malaria

The return of carbon dioxide to the atmosphere and nitrogen to the soil is due to the action of: 1. fungi and viruses. 2. fungi and bacteria. 3. viruses and plants. 4. plants and bacteria. 5. bacteria and viruses.

2. fungi and bacteria.

Lice and mites... 1. cause Lyme disease. 2. may both be spread by personal contact. 3. are both arachnids. 4. are intestinal parasites. 5. both cause respiratory illness.

2. may both be spread by personal contact.

Once Y. pestis is in the human host, it is ingested by macrophages. Conditions within the macrophage activate certain genes in the bacterium, one of which is a gene for a capsule production. The capsule: 1.allows the bacteria to survive excess heat. 2.allows the bacteria to avoid phagocytosis. 3.provides a source of nutrients for the bacteria. 4. allows the bacteria to float in water. 5.allows the bacteria to exchange DNA with other bacteria.

2.allows the bacteria to avoid phagocytosis.

How many nucleotides are in a codon? 1 2 3 4 5

3

Without changing the sequence or the orientation of the sequence(s), which is/are complementary to the sequence 5' AGGCUAAC 3'? 3' TCCGATTC 5' AND 5' CTTAGCCT 3' 5' TCCGATTG 3' 3' TCCGATTG 5' 3' TAAGCTTA 5' 5' CTTAGCCT 3'

3' TCCGATTG 5'

Protozoans are an important part of the food chain, ingesting large numbers of: 1. other protozoans. 2. bacteria and fungi. 3. bacteria and algae. 4. fish and crabs. 5. shellfish and algae.

3. bacteria and algae.

Sarcodina move by means of: 1. microvilli. 2. apicomplexans. 3. pseudopodia. 4. flagella. 5. cilia.

3. pseudopodia.

The time from absorption to release for T-even phage is about - 1 minute. - 10 minutes. - 30 minutes. - 45 seconds. - 1 day.

30 minutes.

Identify the correct sequence in which the steps below occur during a single PCR cycle. 1. Complementary base pairing between primers and target DNA. 2. Addition of DNA nucleotides by Taq DNA polymerase. 3. Heat separation of strands of target DNA. 1; 2; 3 2; 1; 3 2; 3; 1 3; 1; 2 1; 3; 2

3; 1; 2

Select the TRUE statement regarding algae. 1. Algae are plants and therefore possess a highly organized vascular system. 2. Algae are generally saprophytic, living off dead and decaying matter. 3. Some algae can directly cause infectious diseases in humans and other animals. 4. Although most algae have a cellulose/pectin cell wall, some algae lack a cell wall. 5.Algae always reproduce sexually, producing both haploid and diploid generations.

4. Although most algae have a cellulose/pectin cell wall, some algae lack a cell wall.

The pH at which most fungi thrive is ________.

5 - some fungal species can grow in concentrations of salts, sugars or acids that inhibit the growth of most bacteria. Fungi can grow on pH 2.2-9.6 and usually grow well at pH 5.0 or lower.

Which disease is INCORRECTLY matched with its arthropod vector? 1. Dengue fever—mosquitoes 2. Malaria—Anopheles mosquito 3. Lyme disease—ticks 4. Plague—fleas 5. African sleeping sickness—sand fly

5. African sleeping sickness—sand fly

There are ________ major families of DNA-containing viruses that infect vertebrates.

7

Starting with a single piece of dsDNA, after 3 PCR cycles there are 4 additional pieces of dsDNA. 8 additional pieces of dsDNA. 1 additional piece of dsDNA. 16 additional pieces of dsDNA. 2 additional pieces of dsDNA.

8 additional pieces of dsDNA.

A three base sequence on mRNA is called a(n) a. codon. b. exon. c. anticodon. d. intron.

A

All fungi have __________ in their cell walls: A. chitin. B. pectin. C. peptidoglycan. D. phospholipids. E. cellulose.

A

All of the following pertain to transcription except a. occurs on a ribosome in the cytoplasm. b. occurs before translation. c. requires RNA polymerase. d. requires a template DNA strand. e. proceeds in the 5' to 3' direction of the growing mRNA molecule.

A

Amplification of DNA is accomplished by a. polymerase chain reaction. b. DNA sequencing. c. gene probes. d. southern blot. e. western blot.

A

DNA Polymerase I a. removes primers. b. adds bases to new DNA chain. c. supercoils DNA. d. unzips DNA. e. synthesizes RNA primer.

A

Negative control means that a regulator molecule is A. bound and transcription is inhibited AND removed and transcription begins. B. bound and transcription is inhibited. C. bound and transcription begins. D. removed and transcription begins. E. removed and transcription begins.

A

Okazaki fragments are attached to the growing end of the lagging strand by a. DNA ligases. b. DNA polymerases. c. DNA helicases. d. DNA gyrates e. primases.

A

Organisms that grow very slowly, are non-culturable, are present in very small numbers, or are mixed with a number of bacteria may still be identified using: A. PCR. B. Southern blotting. C. colony blotting. D. replica plating. E. gas chromatography of fatty acids.

A

Propionibacterium A. produces propionic acid. B. produces lactic acid. C. is responsible for the blue color of Stilton cheese. D. requires aerobic environments. E. produces propionic acid and is responsible for peptic ulcers.

A

The nontranscribed region of DNA to which RNA polymerase binds to initiate transcription is called the a. promoter. b. operator. c. operon. d. exon. e. intron.

A

The placement of the amino acid during translation is determined by the: A. complementarity of the codon-anticodon. B. DNAse which transcribes both molecules. C. sequence of nucleotides at the 5' end of the tRNA. D. 16S rRNA sequence. E. secondary structure of the newly forming protein.

A

The primers in PCR are a. synthetic short strands of DNA (oligonucleotides). b. bacterial enzymes. c. short RNA strands. d. DNA polymerases. e. reverse transcriptases.

A

The size of the amplified DNA fragment generated during PCR is determined by A. the locations to which the primers anneal. B. how many cycles are performed. C. the size of the template DNA. D. how much Taq polymerase is used.

A

The various techniques by which scientists manipulate DNA in the lab are called a. genetic engineering. b. biotechnology. c. recombinant DNA. d. gel electrophoresis. e. gene probes.

A

Thymine dimers are dealt with by A. Photoreactivation repair AND excision repair B. Excision repair C. SOS repair D. No repair mechanisms E. Photoreactivation repair

A

What type of mutation alters the base, but not the amino acid being coded for? a. silent b. back c. point d. nonsense e. missense

A

Which PCR step synthesizes complimentary DNA strands? a. add DNA polymerase and nucleotides at 72°C b. cool DNA to between 50°C and 65°C c. add primers d. heat target DNA to 94°C e. repeat the cycle of heating and cooling

A

Which is incorrect about purines? a. only found in DNA, not in RNA b. are nitrogenous bases c. always paired with a specific pyrimidine d. include adenine and guanine e. found within nucleotides

A

A student complains that it makes no sense to worry about coliform bacteria in water, since we naturally possess harmless coliforms in our intestines anyway. Why do regulatory agencies worry about coliform bacteria in water supplies, then? A. Not all coliforms are harmless and symbiotic with human beings and some may carry genes/proteins that can make them dangerous to humans; it is best to keep coliforms OUT of our drinking water, since it is difficult to identify which ones might be harmless and which ones might be harmful. B. Regulatory agencies simply need something to do to justify their existence; there is no real danger from coliforms in water supplies. C. The coliforms in our intestines can sometimes turn harmful, causing intestinal infections; we need to constantly be on guard against this happening; coliforms in water might add to this potential problem. D. Regulatory agencies are worried that multiple types of coliforms in water might lead to greater antibiotic resistance in the bacterial populations; they try to keep them out of water to keep antibiotic resistance levels down.

A - B and D are just silly, and 'constantly on guard' in C = nope. coliforms refers to enterics - are an indicator that the water could be contaminated with fecal matter.

Single-celled eukaryotic organisms that lack chlorophyll are called A. protozoa. B. saprophytes. C. algae. D. Chlorophyta. E. Salmonella.

A - Eurkaryotes we talked about - fungi, algae, protozoa, slime mold, water mold - Single celled and no chlorophyll adds up to protozoa.

Polymerase chain reaction (PCR) can be used to perform DNA sequencing reactions. In this case, are 2 primers (a forward and a reverse) necessary? A. No; dideoxynucleotide sequencing depends on different length fragments being formed and then separated based on size and this can take place with only a specific forward primer OR a specific reverse primer. B. No; you actually need a primer pair for each round of DNA amplification and so you will need many, many primer pairs. C. Yes; it will be important to make sure that the primer pairs are made with dideoxynucleotides that are labeled with fluorescent dyes otherwise you will not be able to detect the fragments that are made in the PCR process. D. Yes; PCR cannot be performed without 2 specific primers to amplify the region in question in the DNA

A - I got this one wrong once before. Still not sure I understand this one but it is A.

In E. coli 0157:H7 the 0157:H7 refers to the A. specific LPS and flagella type present. B. specific biotype. C. specific type of DNA present. D. general family. E. specific genus.

A - O antigen is on LPS in out membrane of G- bacteria - H refers to the flagella type - K refers to the capsule

The agarose used in electrophoresis: A. acts as a sieve. B. interacts electrically with the DNA. C. chemically binds to the DNA. D. selectively sorts recombinant DNA from host DNA.

A - does not change the DNA at all, just lets the fragments move through it.

The lactobacilli, in their role as normal flora of the vagina, help it resist infection by contributing to: A. the acidity of the vagina. B. fertility of the host. C. food for the resident vaginal flora. D. urease production. E. the neutrality of the vaginal muscles.

A - lactic acid bateria. Breaks down glycogen deposited in vaginal walls due to estrogen and lowers the pH to prevent bacterial overgrowth.

Viruses acquire envelopes around their nucleocapsids during: A. release. B. assembly. C. penetration. D. adsorption. E. replication.

A - lipid bilayer with virus and host proteins

To maximize the number of thymine dimer mutations following UV exposure, should you keep a plate of fungal cells in the dark, in the light, or does it matter at all? A. It does not matter; fungal cells do not possess the enzymes needed for photorepair of thymine dimers because these enzymes are only found in prokaryotes. B. It is best to alternate light and dark every hour to increase the chances that thymine dimers will form in the fungal cells, but still keep the photorepair systems from correcting them as they are formed. C. Keep then in the dark; light will activate the photorepair systems that can break the thymine dimers induced by UV light. D. Keep them in the light; it is important to keep on producing thymine dimers by keeping the plate exposed to light as much as possible.

A - options for repair are light repair (photorepair - in PROKARYOTES only), dark repair {excision repair), SOS repair when the damage is terrible - means C would be true IF it was PROKARYOTES

Post-translational modification may include: A. the folding of the protein, often with the aid of chaperones AND the removal of the signal sequence B. removal of the signal sequence. C. the folding of the protein often with the aid of chaperones. D. the formation of exons and introns. E. the addition of glycine tags.

A - proteins don't stay in long strings, they have to fold up. Signal sequence is on proteins destined to outside the cell and the sequence is taken off as it moves through the cytoplasmic membrane.

What structure is indicated by: 10A, 15T, 3G, 7C? A. Single-stranded DNA. B. Double-stranded DNA. C. Double-stranded RNA. D. Single-stranded RNA.

A - still haven't seen mention of this in the text.

The lagging strand: A. is necessary due to the properties of the enzymes and the antiparallel nature of DNA. B. is always the bottom strand. C. is found during RNA replication. D. is the third type of RNA. E. iIs the strand always associated with the primer.

A -Also, is still replicated along the 3 to 5 direction since DNA polymerase works in 5 to 3 direction. Results in Okazaki fragments - another polymerase will replace the RNA primer with DNA and DNA ligase will covalently bond the nucleotides together.

Scientists have cloned the human insulin gene into E. coli. Which of the following would NOT have been used in the procedure? A bacteriophage DNA ligase Competent bacteria A restriction enzyme A plasmid

A bacteriophage

Which statement regarding phage replication is TRUE? - Lambda can be a lytic or a temperate phage. - Lambda is a good example of a lytic phage. - When integrated into host DNA, phage DNA is called a virophage. - A lysogen is a virus that has bacterial DNA in it. - A lysogen is a bacterial cell with an integrated prophage.

A lysogen is a bacterial cell with an integrated prophage.

Rhizobium - fix nitrogen inside nodules on the roots of legumes.

A symbiotic bacterium that lives in the nodules on roots of specific legumes and that incorporates nitrogen gas from the air into a form of nitrogen the plant requires

Phages that can either replicate and cause cell lysis or can integrate their DNA into the host DNA are called

A temporate phage.

Which of the following is NOT true about an ideal vector? A vector has a restriction enzyme recognition site. A vector contains an origin of replication. A vector contains a selectable marker. A vector contains an RNA primer. A vector may be a plasmid or bacteriophage.

A vector contains an RNA primer.

The three domain classification scheme uses A. Archaea, Bacteria, Eukarya. B. Protista, Prokaryotae, Fungi. C. Plants, Animals, Bacteria. D. order, phylum, class. E. Bacteria, Archaea, Animalia

A. Archaea, Bacteria, Eukarya.

A.Wherein a parasite sexually reproduces B. Taxonomic category of related organisms, usually containing several species; the first name of an organism in the Binomial System of Nomenclature C. Flowchart of tests used for identifying an organism; each test gives either a positive or negative result D. Characteristic structures of motility in spirochetes E. The group of Gram-negative oxygenic phototrophs genetically related to chloroplasts

A. Definitive Host B. Genus C. Dichotamous Key D. Endoflagella E. Cyanobacteria

A. A type of horizontal gene transfer occuring when a phage carries a random piece of bacterial DNA acquired when a packaging error occurs during the assembly of phage particles B. Infection that develop slowly and persist for months or years C. Characterized by a lipid bilayer surrounding the nucleocapsid D. The modification of cell properties resulting from expression of phage DNA integrated into a bacterial chromosome E. Infection in which the infectious agent is present but not active

A. Generalized Transdution B. Chronic Infection C. Enveloped Virus D. Lysogenic Conversion E. Latent Infection

You suspect that she may have Helicobacter pylori gastritis, and send her for a urea breath test. The breath test is positive; based on this, you get the patient's stool tested for blood, and you send her for an endoscopy, during which a biopsy is taken. Your diagnosis is confirmed by the results of these tests and that she does indeed have H. pylori. Your patient asks you how a bacterium can survive in her stomach, which she knows is very acidic. You explain that: A. H. pylori produces urease that converts urea into carbon dioxide and ammonia; the ammonia neutralizes the pH of the stomach, allowing the bacteria to survive. B. H. pylori is an acidophile, and as such prefers acidic pH levels of 1-3; gastric juices contain hydrochloric acid which has a very low pH. C. H. pylori is encased in the very thick polysaccharide capsule that protects it from the degradative effects of the HCl found in the stomach. D. H. pylori forms a biofilm with the other normal microbiota of the stomach. The structure of the biofilm covers and protects the bacteria within it. E H. pylori has the ability to form endospores in hostile environmental conditions. It does this in the acidic stomach, only germinating once they reach the small intestine.

A. H. pylori produces urease that converts urea into carbon dioxide and ammonia; the ammonia neutralizes the pH of the stomach, allowing the bacteria to survive.

Wisconsin state health authorities alerted the CDC about an E. coli O157:H7 outbreak. Soon thereafter, officials from two other states reported that they also had cases of illness associated with this pathogen. Within days, the CDC determined that the E. coli strains from all three states were the same, and the likely source of the outbreak was a particular brand of pre-packaged fresh spinach. The CDC then issued a press release advising people not to eat bagged fresh spinach. Please select the FALSE definition regarding microbial identification: A. RFLPs are patterns of fragment sizes obtained by digesting polypeptides with one or more proteases. B. A signature sequence is a nucleotide sequence in rRNA that characterizes a certain species or a group of related organisms. C. A biotype is a group of strains that have a characteristic biochemical pattern different from other strains. D. A species is a group of closely related strains; it is the basic unit of taxonomy. E. A serovar is a group of strains that have a characteristic antigenic structure that differs from other strains.

A. RFLPs are patterns of fragment sizes obtained by digesting polypeptides with one or more proteases.

A. In virology, the separation of the protein coat from the nucleic acid of the virion B. The structures on the outside of the virion that bind to host cell receptors C. The group of viruses possessed of a single-stranded RNA genome; their enzyme, reverse transcriptase, synthesizes a DNA copy that is then integrated into the host cell chromosome D. The group of fatal neurodegenerative diseases in which brain tissue develops sponge-like holes E. The viral particle in its inert, extracellular form

A. Uncoating B. Spikes (attachment proteins) C. Retroviruses D. Transmissible Spongiform Encephalopathies (TSE's) E. Virion

Chemoheterotroph (energy source + carbon source)

A. Uses chemical reactions for energy and uses organic compounds

A.In molecular biology, a piece of DNA acting as a carrier of a cloned fragment of DNA; in epidemiology, any living organism that can carry a disease-causing microbe, most commonly arthropods such as mosquitoes and ticks B. Organism utilizing nutrients from dead and decaying matter C. Isolated from Agrobacterium tumefaciens, it allows those organisms to cause tumors in plants; a derivative is used as a vector to introduce DNA into plants by genetic engineering D. Pattern of fragment sizes obtained by digesting DNA with one or more restriction enzymes E. Evolutionary relatedness of organisms

A. Vector B. Saprophyte C. Tumor-inducing (Ti) plasmid D. Restriction fragment length polymorphism (RFLP) E. Phylogeny

How do all viruses differ from bacteria? A)Viruses are not composed of cells. B)Viruses do not have any nucleic acid. C)Viruses are obligate intracellular parasites. D)Viruses do not reproduce. E)Viruses are filterable.

A. Viruses are not composed of cells. - viruses are not cells, are not alive, are acellular infectious agents.

Purple sulfur bacteria and filamentous sulfur-oxidizers both: A. accumulate sulfur as intracellular granules. B. fix nitrogen. C. produce oxygen from carbon dioxide. D. use gliding motility

A. accumulate sulfur as intracellular granules.

A. A poisonous substance made by Aspergillus flavus B. Lacking O2 C. Microbiological group of strains having a characteristic biochemical pattern different from other strains; also called a biovar D. Biological production of light E. Organism that obtains energy by oxidizing organic compounds such as glucose

A. aflatoxin B. anoxic C. biotype D. bioluminescense E. chemoorganotroph

The point at which two organisms diverged from a common ancestor: A. can be determined by comparing the nucleic acid sequences. B. is determined on MacConkey's media. C. depends on transcriptional and translational control. D. depends on metabolic activity and antibiotic resistance. E. is impossible to determine.

A. can be determined by comparing the nucleic acid sequences.

A. Protein coat surrounding the nucleic acid of a virus B. Major change in a viral surface antigen that render antibodies made against the previous version ineffective C. Illness characterized by signs and symptoms that develop quickly but last a relatively short time D. Arthropod-borne virus; one of a large group of RNA viruses carried by insects and mites that act as biological vectors E. A virus that infects bacteria; often abbreviated to phage

A. capsid B. Antigenic shift - shift is a MAJOR change whereas drift is a minor change. C. Acute Infection D. Arbovirus E. Bacteriophage

APITM, EnterotubeTM, and VitekTM are all: A. commercially available methods used to identify bacteria. B. methods for extracting protein from bacteria. C. used to show the presence of bacteria in a sample. D. methods for extracting DNA from bacteria. E. used to measure gas production.

A. commercially available methods used to identify bacteria. (kits or computerized analysis designed to make metabolic capability testing quick and easy.)

Agrobacterium : A. contain the Ti plasmid which modifies the growth of plant tissue. B. produce antibiotics. C. infect animal cells. D. resemble fungus.

A. contain the Ti plasmid which modifies the growth of plant tissue.

Swarmer cells are: A. formed by sheathed bacteria. B. also known as coliforms. C. part of the green non-sulfur bacteria. D. formed by Myxobacteria. E. used in sewage treatment.

A. formed by sheathed bacteria

Disagreements between conclusions obtained from rRNA/rDNA data and other techniques may be explained by: A. horizontal DNA transfer. B. vertical DNA transfer. C. differences in post-replication modification. D. the difference in translation machinery. E. vertical RNA transfer.

A. horizontal DNA transfer.

Which of the following is not true about mismatch repair? A. it removes both strands in the mismatch area B. it utilizes the state of methylation of the DNA to differentiate between strands C. it requires DNA polymerase and DNA ligase D. it utilizes an endonuclease

A. it removes both strands in the mismatch area [it only removed ONE strand]

You tell the patient that his sample contains white blood cells in which Gram-negative diplococci can be detected. Your patient asks how you obtained this result and you tell him you: A. performed a Gram stain. B. cultured his discharge on Gram-negative medium. C. cultured his discharge on Gram-positive medium. D. performed an antibiogram. E. performed an acid-fast stain.

A. performed a Gram stain.

A. The clear area in a monolayer of cells B. The protein that when bound to the operator site prevents transcription C. The latent form of a temperate phage whose DNA has been inserted into the host DNA D. Infectious protein causing a neurodegenerative disease E. A viral infection causing the host cell to lyse

A. plaque B. Repressor C. Prophage D. prion E. Lytic infection

Two isolates with identical RFLPs are considered: A. possibly the same strain. B. identical. C. different strains. D. different genera. E. definitely the same strain.

A. possibly the same strain.

Match each component with its correct application: 1. Chaperone 2. sigma factor 3. inducer 4. repressor 5. primer A. replication B. transcription C. post-transcription

A. replication -- 5. primer B. transcription -- 2. sigma factor, 3. inducer, 4. repressor C. post-transcription - 1. chaperone

A DNA similarity of 75% between two organisms: A. suggests the organisms are closely related at the species level. B. suggests the organisms may or may not be related. C. suggests the organisms are not closely related at all. D. means the GC content in both organisms is 45%. E. means the GC content in one organism is 75% and 25% in the other.

A. suggests the organisms are closely related at the species level.

Nucleic acid techniques have great power as diagnostic tools because they may be A. very specific. B. quick and easy to perform. C. used to enhance the growth of bacteria. D. used to selectively inhibit the growth of certain bacteria.

A. very specific.

A. Phototrophic organism producing O2 B. A common name for members of the family Enterobacteriaceae C. Roundworms D. The group of Gram-positive bacteria generating lactic acid as the major end product of their fermentive metabolism E. A method of distinguishing strains that relies on determining the nucleotide sequence of select DNA regions

A.Oxygenic phototroph B. Enterics C. Nematodes D. Lactic Acid Bacteria E. Multilocus Sequence Typing

If you examined the acidic runoff from a coal mine, which of the following would you most likely find grow there?

Acidithiobacillus

A graduate student is trying to isolate bacterial mRNA for an enzyme that will degrade trinitrotoluene (TNT). She's frustrated to find that the enzyme isn't produced when the bacterium in question is grown on nutrient agar. What might she do to solve the problem and obtain the mRNA? Remove glucose from the agar—this will cause the bacteria to shift to other compounds for their energy purposes. Remove nitrogen and toluene from the agar which will lead to driving up synthesis of TNT, leading to production of the mRNA the student is looking for Add TNT to the agar—this will drive synthesis of the enzyme to degrade it, leading to production of the mRNA the student is looking for. Remove TNT from the nutrient agar; it acts as an inhibitor of all microbial growth, and prevents the bacteria from synthesizing any enzymes at all. Add nitrogen and toluene to the agar which will drive up synthesis of TNT, leading to production of the mRNA the student is looking for.

Add TNT to the agar—this will drive synthesis of the enzyme to degrade it, leading to production of the mRNA the student is looking for.

Which change in a gene's DNA sequence would have the least effect on the eventual amino acid sequence produced from it? - Sub of 1 nucleotide AND add of 1 nucleotide - Add of 1 nucleotide - Addition/deletion of 3 consecutive nucleotides - Sub of 1 nucleotide - Deletion of 2 consecutive nucleotides

Addition/deletion of 3 consecutive nucleotides

Sulfolobus species are found at the surface of acidic sulfur-containing hot springs such as many of those found in Yellowstone National Park. They only grow at temperatures above 50°C and at a pH between 1 and 6. How would you classify these organisms? - Psychrotrophic neutrophiles - Aerobic, psychrophilic acidophiles - Anaerobic, acidophilic mesophiles - Microaerophilic, halotolerant basophiles - Aerobic, acidophilic thermophiles

Aerobic, acidophilic thermophiles

Which of the following genera has proved useful for manipulating plant cells? Pseudomonas Bacillus Agrobacterium Escherichia Rhizobium

Agrobacterium

Members of this group generally don't cause infections, but some produce neurotoxins that cause intoxications in animals that consume them. Members of this group are found predominantly in aquatic environments.

Algae

Why is it virtually impossible to eradicate a disease caused by a zoonotic virus? - You would have to drive the vector organism extinct to do so. - Many viruses transmitted in this manner may utilize more than one vector organism. - Many zoonotic viruses may be able to reside in more than one host organism, complicating control measures. - Many vector organisms have multiple stages of their life cycle that can carry a zoonotic virus, which complicates controlling the vector-borne transmission. - All of the answer choices are correct.

All are correct.

Prions - replicate by converting normal host proteins into prion proteins. - responsible for "mad cow disease" can cause a similar disease in humans. - can be transmitted by consumption of dried or cooked food. - that cause Spongiform Encephalopathy have the same amino acids - but different folding properties from PrPc. - all of the above

All of the above.***

Genetic engineering of plants has so far produced plants with increased nutritional value. pest-resistant plants. plants that are herbicide resistant. All of the answer choices are correct. None of the answer choices is correct.

All of the answer choices are correct.

Fungi are important in: - food production. - disease of plants. - food spoilage. - production of antibiotics. - All of the choices are correct.

All of the choices are correct.

Transposons are informally known as jumping genes. may cause insertion mutations. may cause knockout mutations. were first recognized in plants. All of the choices are correct.

All of the choices are correct.

Which is not true about a crown gall tumor? It is a bacterial infection of plants. It requires a plasmid. It produces a large amount of opines that neither the plant nor bacteria synthesizes. It is due to the incorporation of bacterial plasmid DNA into the plant chromosome. All of the choices are true.

All of the choices are true

Plant viruses may be transmitted by: - humans. - worms. - insects. - contaminated seeds. - All of the choices are correct.

All the choices are correct

Coliforms: - are an informal grouping of enterics. - ferment lactose. - include E. coli. - are used as indicators of fecal contamination. - All of the choices are correct.

All the choices are correct - enteric = fecal coliform

Luminescence: - may be produced by bacteria. - may be controlled by quorum sensing. - is catalyzed by luciferase. -All of the choices are correct. - None of the choices is correct.

All the choices are correct. - bioluminescence - density-dependent light emission

A quick microbiological test for potential carcinogens was developed by Fleming. Lederberg. Ames. Crick.

Ames

What is a definitive host in the life cycle of a parasite? 1. An organism in which the parasite multiplies asexually, without causing any damage to the host. 2. An organism in which either sexual reproduction or asexual reproduction of the parasite occurs. 3. An organism in which sexual reproduction or the adult form of a parasite occurs. 4. An organism from which a parasite typically is not passed to another host, so that the parasite cannot complete its life cycle. 5.An organism in which asexual reproduction or an immature form of a parasite occurs.

An organism in which sexual reproduction or the adult form of a parasite occurs.

Which of the following genera fix nitrogen?

Anabaena, Azotobacter, and Rhizobium

An enzyme produced in response to the presence of a substrate is called A) An inducible enzyme. B) A repressible enzyme. C) A restriction enzyme. D) An operator. E) A promoter.

Answer: A

An enzyme that copies DNA to make a molecule of RNA is A) RNA polymerase. B) DNA ligase. C) Restriction enzyme. D) Transposase. E) DNA polymerase.

Answer: A

If you knew the sequence of nucleotides within a gene, which one of the following could you determine with the most accuracy? A) The primary structure of the protein B) The secondary structure of the protein C) The tertiary structure of the protein D) The quaternary structure of the protein E) Can't tell

Answer: A

The mechanism by which the presence of glucose inhibits the arabinose operon is A) Catabolite repression. B) Translation. C) DNA polymerase. D) Repression. E) Induction.

Answer: A

Which of the following is NOT a product of transcription? A) A new strand of DNA B) rRNA C) tRNA D) mRNA E) None of the above

Answer: A

An enzyme that makes covalent bonds between nucleotide sequences in DNA is A) RNA polymerase. B) DNA ligase. C) Restriction enzyme. D) Transposase. E) DNA polymerase.

Answer: B

In transcription, A) DNA is changed to RNA. B) DNA is copied to RNA. C) DNA is replicated. D) RNA is copied to DNA. E) Proteins are made.

Answer: B

Transformation is the transfer of DNA from a donor to a recipient cell A) By a bacteriophage. B) As naked DNA in solution. C) By cell-to-cell contact. D) By crossing over. E) By sexual reproduction.

Answer: B

Which of the following pairs is mismatched? A) DNA polymerase - makes a molecule of DNA from a DNA template B) RNA polymerase - makes a molecule of RNA from an RNA template C) DNA ligase - joins segments of DNA D) Transposase - insertion of DNA segments into DNA E) DNA gyrase - coils and twists DNA

Answer: B

Which of the following statements about bacteriocins is false? A) The genes coding for them are on plasmids. B) They cause food-poisoning symptoms. C) Nisin is a bacteriocin used as a food preservative. D) They can be used to identify certain bacteria. E) Bacteriocins kill baceria.

Answer: B

A gene is best defined as A) A segment of DNA. B) Three nucleotides that code for an amino acid. C) A sequence of nucleotides in DNA that codes for a functional product. D) A sequence of nucleotides in RNA that codes for a functional product. E) A transcribed unit of DNA.

Answer: C

According to the operon model, for the synthesis of an inducible enzyme to occur, the A) End-product must not be in excess. B) Substrate must bind to the enzyme. C) Substrate must bind to the repressor. D) Repressor must bind to the operator. E) Repressor must not be synthesized.

Answer: C

An enzyme that cuts double-stranded DNA at specific nucleotide sequences. A) RNA polymerase B) DNA ligase C) Restriction enzyme D) Transposase E) DNA polymerase

Answer: C

Conjugation differs from reproduction because conjugation A) Replicates DNA. B) Transfers DNA vertically, to new cells. C) Transfers DNA horizontally, to cells in the same generation. D) Transcribes DNA to RNA. E) Copies RNA to make DNA.

Answer: C

DNA is constructed of A) A single strand of nucleotides with internal hydrogen bonding. B) Nucleotides bonded A-C and G-T. C) Two strands of nucleotides running antiparallel. D) Two strands of identical nucleotides with hydrogen bonds between them. E) None of the above.

Answer: C

When glucose is high, cAMP is ________ : CAP ________ bind the lac operator, and RNA polymerase ________ bind the lac promoter. A) low, doesn't, doesn't B) high, does, does C) low, doesn't, doesn't D) high, doesn't, does E) low, does, does

Answer: C

Repair of damaged DNA might be viewed as a race between an endonuclease and A) DNA ligase. B) DNA polymerase. C) Helicase. D) Methylase. E) Primase.

Answer: D

Synthesis of a repressible enzyme is stopped by A) The allosteric transition. B) The substrate binding to the repressor. C) The corepressor binding to the operator. D) The corepressor-repressor binding to the operator. E) The end-product binding to the promoter.

Answer: D

The damage caused by ultraviolet radiation is A) Never repaired. B) Repaired during transcription. C) Repaired during translation. D) Cut out and replaced. E) Repaired by DNA replication.

Answer: D

The initial effect of ionizing radiation on a cell is that it causes A) DNA to break. B) Bonding between adjacent thymines. C) Base substitutions. D) The formation of highly reactive ions. E) The cells to get hot.

Answer: D

Which of the following statements is false regarding a bacterium that is R+? A) It possesses a plasmid. B) R+ can be transferred to a cell of the same species. C) It is resistant to certain drugs and heavy metals. D) It is F+. E) R+ can be transferred to a different species.

Answer: D

Which of the following statements is false? A) DNA polymerase joins nucleotides in one direction only. B) The leading strand of DNA is made continuously. C) The lagging strand of DNA is started by an RNA primer. D) DNA replication proceeds in one direction around the bacterial chromosome. E) Multiple replication forks are possible on a bacterial chromosome.

Answer: D

Genetic change in bacteria can be brought about by A) Mutation. B) Conjugation. C) Transduction. D) Transformation. E) All of the above.

Answer: E

Protein synthesis in eukaryotes is similar to the process in prokaryotes in that both eukaryotes and prokaryotes A) Have exons. B) Have introns. C) Require snRNPS. D) Use methionine as the "start" amino acid. E) Use codons to arrange amino acids.

Answer: E

The mechanism by which the presence of arabinose controls the arabinose operon is A) Catabolite repression. B) Translation. C) DNA polymerase. D) Repression. E) Induction.

Answer: E

Which phylum of protozoa contains organisms that are non-motile, obligate intracellular parasites? - Euglenozoa - Amoebozoa - Apicomplexa - ciliates

Apicomplexa

Members of this group have hard exoskeletons and jointed appendages. Members of this group serve as vectors, transmitting several different viruses, bacteria, and protozoan parasites between hosts.

Arthropods

Please select the FALSE statement regarding arthropod vectors. - Mechanical vectors simply transfer a pathogen from one surface to another. - The incidence of vector-borne diseases can be decreased by controlling the vector or the infected hosts. - Biological vectors play an essential role in the life cycle of the pathogen. - Arthropods are very specific and always bite only one type of host. - Some arthropods cause disease even when they do not act as a vector.

Arthropods are very specific and always bite only one type of host.

The material responsible for transformation was shown to be DNA by Watson and Crick. Avery, MacLeod and McCarty. Lederberg. Stanley.

Avery, MacLeod and McCarty.

A common way to identify E. coli that carry the desired recombinant DNA is by using a: A. vector. B. probe. C. host. D. plasmid. E. restriction enzyme.

B

Bacterial conjugation involves a. bacteriophage carrying donor DNA to the recipient cell. b. a donor cell with a plasmid that synthesizes a pilus. c. naked DNA fragments from a lysed donor cell taken up by a recipient cell. d. new progeny cells with genes from two parent bacterial cells. e. None of the choices is correct.

B

Direct selection involves inoculating cells onto growth media upon which A. the nutrients necessary for mutation to occur are present. B. the mutant, but not the parental cell type, will grow. C. the mutagen is present. D. the mutation will be reversed.

B

Disagreements between conclusions obtained from rDNA data and other techniques may be explained by: A. differences in the translation machinery. B. horizontal DNA transfer. C. vertical DNA transfer. D. the lack of DNA polymerase proof-reading. E. vertical RNA transfer.

B

During replication, each parent DNA strand serves as a _____ for synthesis of new DNA strands. a. copy point b. template c. comparison molecule d. scaffold e. reservoir

B

Geneticists can make complimentary DNA from messenger, transfer, and ribosomal RNA by using a. palindromes. b. reverse transcriptase. c. restriction endonucleases. d. ligases. e. DNA polymerases.

B

Genomic _____ are collections of isolated genes maintained in a cloning host. a. DNA b. libraries c. clones d. digests e. books

B

If the G+C content of two organisms is 45% in both A. the A+T content is 65%. B. they may or may not be related. C. they are definitely not related. D. they are definitely related AND the A+T content is 65%. E. they are definitely related.

B

Outside of living cells, viruses are: A. scavenging glucose. B. metabolically inert. C. using cilia to move to the next host. D. slowly stockpiling ATP from the mitochondria.

B

Restriction endonucleases recognize and clip at DNA base sequences called a. codons. b. palindromes. c. introns. d. exons. e. genes.

B

Synthesis of an inducible enzyme requires a. repressor alone bound to operator. b. substrate bound to repressor. c. substrate bound to promoter. d. corepressor and repressor binding to operator. e. None of the choices is correct.

B

The duplication of a cell's DNA is called a. mitosis. b. replication. c. transcription. d. translation. e. mutation.

B

The name Lactococcus (Streptococcus) lactis: A. indicates that Lactococcus is the old class name. B. indicates that Streptococcus is the old genus name. C. indicates that the subgenus is Streptococcus. D. indicates that the family is Lactococcus.

B

The process in which mutations are removed and the correct bases added is called a. transduction. b. excision repair. c. frame shift. d. back-mutation. e. transformation.

B

When DNA probes are used to identify bacterial DNA similarities by hybridization, the probe DNA is heated and the template DNA is treated to separate the 2 strands. Why would the probe DNA be heated? A. DNA hybridization can only take place at high temperatures so all the DNA must be heated up prior to hybridization. B. The probe DNA is single stranded but it may have folded back on itself and formed portions that are double-stranded; heating it up breaks any possible hydrogen bonds that may have formed, returning it to a single-stranded state prior to hybridization. C. Heating up the probe DNA activates the tag on the probe DNA before it hybridizes to the bacterial template DNA D. This is the only way to properly label the probe DNA.

B

Which of the following is incorrect about termination codons? a. where the bond between the final tRNA and the finished polypeptide chain is broken b. include AUG c. include UAA, UAG, and UGA d. do not have corresponding tRNA e. can also be called nonsense codons

B

Wolbachia are found only in A. plants. B. arthropods. C. mammals. D. hot springs. E. fungi.

B

DNA transfer by conjugation is more efficient in a liquid medium setting, subjected to very mild agitation (stirring), rather than on an agar plate format. Why? A. Trick question; it can take place with the same degree of efficiency on either format and it does not matter. B. Direct cell-to-cell contact is required for this process, and this more likely to be achieved in the fluid liquid format than on an agar plate (especially for relatively non-motile types of bacteria) C. Direct cell-to-cell contact is required for this process, and this is more likely to be achieved in the plate format than in the fluid format (especially for relatively non-motile types of bacteria) D. Direct cell-to-cell contact isn't required for this process, so the ability to secrete the DNA into a surrounding fluid medium makes the process more efficient than the dry surface of an agar plate

B - Conjugation, plasmids, DNA transfer - it does require cell-to-cell contact.

Comparatively greater energy is released when: A. carbon dioxide is the final electron acceptor. B. oxygen is the final electron acceptor. C. sulfur is the final electron acceptor. D. hydrogen is the final electron acceptor. E. nitrate is the final electron acceptor.

B - there is a chart in Ch3 that shows how the differences in electronegativity between electron donors and terminal electron receptors determine how much energy is released. Oxygen is way at the bottom, MAX energy released what it is the final electron acceptor.

Operon(s) in bacteria: A. are also known as Wagnerons. B. refers to a group of genes that are coordinately controlled AND involve polycistronic mRNA. C. involve monocistronic mRNA. D. involve polycistronic mRNA. E. refers to a group of genes that are coordinately controlled.

B - remember that eukaryotes have monocistronic mRNA - codes for 1 gene.

Which statement concerning viral structure is true? A) The proteins in the envelope are capsomeres. B) Spikes are found on some viruses. They are very consistent in structure and can be used for identification. C) Animal viruses usually contain tail sheaths and spikes. D) All viruses contain an envelope, which is made of lipid, carbohydrate, and protein.

B) Spikes are found on some viruses. They are very consistent in structure and can be used for identification.

The methanogens, produces of methane gas, require environments that A) have abundant oxygen and CO2 B) are anaerobic with hydrogen gas and CO2 C) are extremely cold D) have sunlight E) are very acidic

B) are anaerobic with hydrogen gas and CO2

2) A feature that may be found in viruses but never in bacteria is A) the ability to pass through 0.22 micrometer pore filters. B) may contain an RNA genome. C) they cannot reproduce themselves outside a host. D) a sensitivity to antibiotics. E) an ability to infect more than one type of host.

B) may contain an RNA genome.

Trichomonas vaginalis can be distinguished from other parasitic protozoa by which of the characteristics listed below? A-It is usually found in drinking water and is associated with fecal contamination. B-It has an undulating membrane, infects the vagina, and is frequently transmitted by sexual contact. C-It is a photosynthetic organism that lives in fresh water. D-It infects Anopheles mosquitoes and can be transmitted by a bite.

B-It has an undulating membrane, infects the vagina, and is frequently transmitted by sexual contact.

To study the phylogeny of eukaryotes, A. 80S rRNA is used. B. 18S rRNA is used. C. 40S rRNA is used. D. 16S rRNA is used. E. 70S rRNA is used.

B. 18S rRNA is used.

67. Relatively little is known about many obligate anaerobes. Why might this be so? A. The obligate aerobes are far more numerous, and also ...cont B. It's much harder to provide the right atmospheric ...cont C. Only obligate aerobes cause disease, so we've had ...cont D. The majority of obligate anaerobes are very ...cont

B. It's much harder to provide the right atmospheric ...cont

Which of the following statements about members of the family Enterobacteriaceae is NOT true? A. It includes many medically relevant bacteria. B. Members only reside in the intestinal tract of humans. C. It includes E. coli, Enterobacter, Salmonella, and Shigella. D. Members are facultative anaerobes. E. All of the choices are correct.

B. Members only reside in the intestinal tract of humans. -members also reside in the intestinal tract of animals and in the soil

Intracellular Gram-negative diplococci found in a urethral sample from a male is indicative of: A. Pseudomonas aeruginosa. B. Neisseria gonorrhoeae. C. Streptococcus pneumoniae. D. Staphylococcus epidermidis.

B. Neisseria gonorrhoeae. (used a microscope to see this - sometimes microscopic morphology is enough to diagnose eukaryotic infections)

Cyanobacterium (energy source + carbon source)

B. Uses light energy and uses carbon dioxide

Photoautotroph (energy source + carbon source)

B. Uses light energy and uses carbon dioxide

Serological methods: A. can rarely be used to identify bacteria. B. are useful in identifying bacteria. C. rely on the specificity of an antibody-antibody interaction. D. may be simple but are always time consuming. E. All of the answer choices are correct.

B. are useful in identifying bacteria.

The earliest oxygenic phototrophs are thought to be: A. purple non-sulfur bacteria. B. cyanobacteria. C. cyanoarchaea. D. green non-sulfur bacteria. E. purple sulfur bacteria.

B. cyanobacteria

DNA probes have been very useful in A. coding the DNA of organisms grown in vivo. B. identifying organisms in pure culture. C. detecting toxins. D. diagnosing diseases of protozoa.

B. identifying organisms in pure culture.

Streptococcus pyogenes: A. may form endospores. B. is beta-hemolytic. C. is alpha-hemolytic. D. is gamma-hemolytic. E. is alpha-hemolytic AND may form endospores.

B. is beta-hemolytic

Sphaerotilus and Leptothrix are examples of A. purple sulfur bacteria. B. sheathed bacteria. C. prosthecate bacteria. D. Enterobacteriaceae. E. green non-sulfur bacteria.

B. sheathed bacteria

A male patient comes to the clinic where you work complaining of urethral discharge and pain on urination. He has recently had unprotected sex with someone he met at a party. You take a sample of the urethral discharge for analysis. Based on the Gram stain results, you tell your patient that you think he has gonorrhea, a sexually transmitted infection (STI) caused by the bacterium Neisseria gonorrhoeae. You are able to make this diagnosis based on: A. signs and symptoms AND the fact that there are bacteria in the urethral discharge. B. signs and symptoms AND because N. gonorrhoeae is the only Gram-negative diplococcus found within white blood cells in the male urethra. C. signs and symptoms AND the fact that bacteria in the discharge are Gram-positive. D. the fact that bacteria are present in red blood cells AND because N. gonorrhoeae is the only Gram-negative diplococcus found within the male urethra. E. the fact that N. gonorrhoeae is the only Gram-negative diplococcus found within white blood cells in the male urethra.

B. signs and symptoms AND because N. gonorrhoeae is the only Gram-negative diplococcus found within white blood cells in the male urethra.

In higher organisms, successful mating can occur between members of the same A. genus. B. species. C. class. D. order.

B. species

The basic taxonomic unit in the classification scheme of plants and animals is:

B. species

The more closely related two organisms are, A. the less they look alike. B. the more similar the nucleic acid sequence. C. the less similar the nucleic acid sequence. D. the more they are phenotypically similar. E. the more similar the nucleic acid sequence AND the more they are phenotypically similar.

B. the more similar the nucleic acid sequence

A graduate student wants to clone a particular gene into a plasmid. The sequence includes AluI and BamHI sites on both sides of the desired fragment. AluI cuts symmetrically directly between the G and C nucleotides in a palindromic 5' AGCT 3' sequence. BamHI cuts asymmetrically directly between the G and G nucleotides in a palindromic 5' GGATCC 3' sequence. Which of the two restriction endonucleases should the graduate student choose, and why? BamHI to cut both sides—since this enzyme cuts asymmetrically, it'll leave the sticky, cohesive single-strand DNA ends that will make it easier to ligate into a BamHI-cut plasmid DNA sequence. Neither of these endonucleases will really be useful; she should look for a single enzyme that creates either blunt ends or sticky ends, depending on the plasmid that she is using as a vector. BamHI on one side of the fragment, and AluI on the other side—this would keep the fragment from sticking right back to where it was cut out from in the original DNA. AluI to cut both sides—it's always easier to ligate together blunt ends of DNA. She should also use AluI on the plasmid she wants to put the fragment into. BamHI on the fragment, and AluI on the plasmid—this will give her the matching sequences to anneal/ligate together on the fragment/plasmid combination.

BamHI to cut both sides—since this enzyme cuts asymmetrically, it'll leave the sticky, cohesive single-strand DNA ends that will make it easier to ligate into a BamHI-cut plasmid DNA sequence.

The report that genes direct the synthesis of proteins was first made by Beadle and Tatum. Lederberg. Curie. Mendel. Watson and Crick.

Beadle and Tatum.

All of the following genera are spirochetes:

Borrelia, Leptospira, Spirochaeta, Treponema CAULOBACTER IS NOT A SPIROCHETE

During PCR, which primer anneals to template DNA at its 3' end? Either the forward primer or the reverse primer. Primers don't bind to template DNA. Both the forward primer and the reverse primer. The forward primer only. The reverse primer only.

Both the forward primer and the reverse primer.

strong chemical mutagens may be used to treat cancer cells. is this a good or a bad idea?

Both; the mutagens are very good at killing cancer cells, but can also be a danger to non-cancerous cells depending on the mode of administration

A permanent, inheritable change in the genetic information is called a. translation. b. transcription. c. mutation. d. alteration. e. regeneration.

C

Bacteria use ___________ attached to the polymerase and they direct RNA polymerase to promoters; eukaryotic cells use __________ that instead attach directly to the DNA first. A. transcription factors; sigma factors B. tRNA; rRNA C. sigma factors; transcription factors D. ribosomes; sigma factors

C

DNA polymerases used in PCR a. use an RNA template to make complementary DNA. b. must remain active at very cold temperatures. c. include Taq polymerase. d. are labeled with fluorescent dyes. e. All of the choices are correct.

C

DNA strands can be clipped crosswise at selected positions by using enzymes called a. palindromes. b. reverse transcriptase. c. restriction endonucleases. d. ligases. e. DNA polymerases.

C

Each _____ is a specific segment of the DNA with the code for production of one functional product. a. intron b. exon c. gene d. operator e. triplet

C

EcoRI and HindIII are a. palindromes. b. reverse transcriptase. c. restriction endonucleases. d. ligases. e. DNA polymerases.

C

Full induction of the lactose operon requires a. lactose present. b. lactose and glucose present. c. lactose present without glucose. d. lactose and arabinose present. e. All of the choices induce the lactose operon.

C

Gene regulation can involve a protein repressor that blocks _____ from initiating transcription. a. DNA polymerase I b. DNA polymerase III c. RNA polymerase d. mRNA e. rRNA

C

If the wild-type DNA sequence reads THE CAT ATE THE BIG RAT, what type of mutation would change the sequence to THE CAT ATA ETH EBI GRA T? a. missense b. nonsense c. insertion d. deletion e. silent

C

Phages that can either replicate and cause cell lysis or can integrate their DNA into the host DNA are called A. segmented phages. B. virulent phages. C. temperate phages. D. lytic phages. E. acute phages.

C

Replication of DNA begins at a(n) ____ rich area. a. guanine-cytosine. b. uracil-adenine. c. adenine-thymine. d. adenine-cytosine. e. guanine-adenine.

C

The DNA of microorganisms is made up of subunits called a. histones. b. amino acids. c. nucleotides. d. mRNA. e. polymerases.

C

The RNA molecules that carry amino acids to the ribosomes during protein synthesis are called a. ribosomal RNA. b. messenger RNA. c. transfer RNA. d. primer RNA. e. ribozymes.

C

The gene that codes for a protein capable of repressing an operon is called the a. operator. b. structural locus. c. regulator. d. promoter. e. None of the choices is correct.

C

The lactose repressor a. is transcribed with the structural lac genes. b. is activated by binding lactose. c. is inactivated by binding lactose. d. requires lactose for its transcription. e. None of the choices is correct.

C

The most serious type of mutation is a a. point mutation. b. silent mutation. c. frame shift mutation. d. back mutation. e. All the choices are equally serious.

C

The viral envelope resembles the A. prokaryotic cell wall. B. cytoplasm. C. eukaryotic cell membrane. D. capsomere.

C

Three consecutive bases in the DNA of a gene represent the code for one a. protein. b. nucleotide. c. amino acid. d. purine. e. None of the choices is correct.

C

Treponema and Borrelia: A.are endosymbionts. B.are both transmitted by mosquitoes. C.are spirochetes. D. are luminescent. E.are both easily grown on artificial media.

C

Which cell can transfer chromosomal and plasmid genes to a recipient cell by conjugation? a. F+ cell b. F- cell c. Hfr cell d. R cell e. B cell

C

Which of the following is not a type of bacterial DNA recombination? a. transformation b. conjugation c. mitosis d. transduction e. meiosis

C

To increase the proportion of mutants in a population of bacteria one may use: A. a direct selection. B. replica plating. C. penicillin enrichment. D. individual transfer.

C - in INDIRECT SELECTION the mutants and the prototrophs can grow on the same medium so PENICILLIN ENRICHMENT is used to increase the proportion of mutants in the population. On a glucose-salt agar add penicillin which will kill any growing cells, the mutants exist on this medium but don't grow so they are safe. You end up with a higher amount of mutants comparitively and then can move on to replica plating.

Which of the following statements concerning viruses is true? A) Viruses are usually about the same size as bacteria. B) Viruses possess enzymes for protein synthesis and ATP generation. C) The "host range" for a virus is determined by the presence or absence of particular components on the surface of a host cell that are required for the virus to attach. D) Viruses contain both DNA and RNA, and they undergo binary fusion.

C) The "host range" for a virus is determined by the presence or absence of particular components on the surface of a host cell that are required for the virus to attach.

Which of the following statements regarding protozoa is FALSE? A-Some protozoan pathogens are transmitted by arthropod vectors. B-Most protozoa reproduce asexually. C-Nearly all protozoa cause disease. D-Protozoa are common in water and soil. E-Protozoa are unicellular eukaryotes.

C-Nearly all protozoa cause disease.

The reference for taxonomic descriptions of bacteria is A. Gray's Anatomy. B. Websters Manual of Taxonomic Bacteriology. C. Bergey's Manual of Systematic Bacteriology. D. Bacteriology.

C. Bergey's Manual of Systematic Bacteriology. - I had this as a T/F question. - It describes descriptions of all known species.

Which statement regarding the Gram stain is FALSE? A. A Gram stain may give sufficient information to start appropriate antibiotic treatment—for example a Gram-positive diplococcus in sputum is likely to be Streptococcus pneumoniae. B. A Gram stain can sometimes be used to make a diagnosis—for example a Gram-negative diplococcus in WBC from urethral discharge is Neisseria gonorrhoeae. C. Gram staining can be used to differentiate intestinal normal microbiota from pathogens—for example differentiating E. coli from Salmonella enterica. D. In most cases, Gram staining is not sufficient to identify an organism—for example, Gram-positive staphylococci on skin may be either S. aureus or S. epidermidis. E. Medically important bacteria can seldom be identified by Gram staining alone—for example the throat may harbor Streptococcus pyogenes (pathogen) as well as Streptococcus species that are normal microbiota.

C. Gram staining can be used to differentiate intestinal normal microbiota from pathogens—for example differentiating E. coli from Salmonella enterica.

What roles do hydrogen gas and carbon dioxide play in the metabolism of methanogens? A. They use hydrogen gas in respiration, and they use carbon dioxide in photosynthesis. B. Hydrogen gas is their terminal electron acceptor, and carbon dioxide is their energy source. C. Hydrogen gas is their energy source, and carbon dioxide is their terminal electron acceptor. D. Hydrogen gas is their energy source, and carbon dioxide is their carbohydrate source. E. Hydrogen gas is their initial electron acceptor, and carbon dioxide is their energy source.

C. Hydrogen gas is their energy source, and carbon dioxide is their terminal electron acceptor.

Which of the following organisms is the causative agent of Hansen's disease (leprosy)? A. Pseudomonas aeruginosa B. Mycobacterium avium C. Mycobacterium leprae D. Mycobacterium smegmatis

C. Mycobacterium leprae

A soluble greenish pigment is produced by: A. Streptococcus pneumoniae. B. Escherichia coli. C. Pseudomonas aeruginosa. D. Serratia marcescens. E. all streptococci.

C. Pseudomonas aeruginosa. - also there's a fruity smell

You have identified the causative organism of the outbreak as E. coli. In an effort to characterize the strain of the organism involved, you do different tests. The results are as follows: Gram stain—Gram-negative rods; Oxidase test—negative; Lactose fermentation—positive; Serological testing—O157:H7; Colony morphology—smooth, creamy colonies; RFLPs—E. coli O157:H7; Antibiogram—resistant to ampicillin. Which test(s) confirm the identity of the organism at the strain level? A. Lactose fermentation AND oxidase test B. Gram stain AND antibiogram C. RFLPs AND serological testing D. Serological testing AND colony morphology E. Oxidase test AND RFLPs

C. RFLPs AND serological testing

Chemoautotroph (energy source + carbon souce)

C. Uses chemical reactions for energy

Each axial filament is made up of fibrils identical in structure to : A. cilia. B. pili. C. flagella. D. pseudopods.

C. flagella.

The name Lactococcus (Streptococcus) lactis A. indicates that the subgenus is Streptococcus. B. indicates that the family is Lactococcus. C. indicates that Streptococcus is the old genus name. D. indicates that Lactococcus is the old class name.

C. indicates that Streptococcus is the old genus name. - the naming system isn't static. Changing names means for more accurate descriptions but is bad in medical situations when people don't know/remember about the name change.

Mycobacterium tuberculosis is one of the few species of bacteria that A. stains Gram-positive. B. lacks a peptidoglycan cell wall. C. is acid-fast. D. is encapsulated. E. stains Gram-negative.

C. is acid-fast. It is the waxy mycolic acid that prevents stain uptake. Remember that it is stained with carbol fuschin first (mycobacterium shows up red) and everything else is stained with methylene blue (shows blue)

The Euryarchaeota includes all A. known thermophilic extreme acidophiles. B. the bacteria. C. known methanogens. D. green sulfur bacteria.

C. known methanogens.

In 1908 Orla-Jensen suggested that bacteria be grouped according to their A. arrangement. B. morphology. C. physiology. D. Gram stain.

C. physiology.

In the 1930s Kluyver and van Niel proposed a classification scheme based on A. Gram reactions. B. biochemical relationships. C. presumed evolutionary relationships. D. DNA sequences.

C. presumed evolutionary relationships.

Thermus and Deinococcus: A. are both radiation resistant. B. are both Gram-positive. C. survive in extreme environments. D. both serve as the source of Taq polymerase. E. are both thermophilic.

C. survive in extreme environments - Thermus is thermophilic and Deinococcus can survive radiation. . Thermus is G-, Deinococcus is G+ Thermus is the source of Taq polymerase Deinococcus can survive gamma radiation

Nucleic acid techniques have great power as diagnostic tools because they may be: A. used to inhibit the growth of certain bacteria. B. used to enhance the growth of bacteria. C. used to differentiate species. D. quick and easy to perform. E. All of the answer choices are correct.

C. used to differentiate species.

GCCCAAAG is a molecule of DNA OR lipid protein. DNA. RNA. Cannot tell as written.

Cannot tell as written.

Serological methods : - are useful in identifying bacteria. - rely on the specificity of an antibody-antigen interaction. - may be simple and rapid. - All of the choices are correct.

Ch 11 - - All of the choices are correct.

A clever technique that streamlines the identification of auxotrophic mutants is - gas chromatography. - replica plating. - direct selection. - reversion

Ch 11 - Replica plating - auxotroph = a mutant organism (especially a bacterium or fungus) that requires a particular additional nutrient which the normal strain does not.

Reticulate and elementary bodies are two forms in the life cycle of - Mycoplasma. - Caulobacter. - Treponema. - Chlamydia. - Myxobacteria.

Chlamydia

Which of the following genera are obligate intracellular parasites? - Chlamydia, Coxiella, AND Rickettsia - Chlamydia, Mycoplasma, AND Micrococcus - Escherichia AND Erlichia - Mycoplasma, Chlamydia, Coxiella, AND Rickettsia - Chlamydia AND Mycoplasma

Chlamydia, Coxiella, AND Rickettsia

Which of the following contains bacteriochlorophyll? - Streptococcus, Chromatium, Thidictyon - Staphylococcus, Thiospirillum, Thidictyon - Bacillus, Chromatium, Thiospirillum - Escherichia, Chromatium, Thiospirillum - Chromatium, Thiospirillum, Thidictyon

Chromatium, Thiospirillum, Thidictyon

A common vector used for cloning genes is/are A. bacteria. B. viroids. C. nucleotides. D. plasmids. E. viruses.

D

A frame shift is caused by ______ mutations. a. missense and insertion b. missense and nonsense c. nonsense and deletion d. deletion and insertion e. insertion and nonsense

D

Anoxygenic phototrophs: A. produce oxygen AND use the same form of chlorophyll found in terrestrial plants. B. produce oxygen. C. use water as a source of electrons D. use hydrogen sulfide or organic compounds as a source of electrons. E. use the same form of chlorophyll found in terrestrial plants.

D

Base pairs in DNA are held together by _____ bonds. a. peptide b. nonpolar covalent c. polar covalent d. hydrogen e. sulfhydryl

D

DNA fragments can be separated in gel electrophoresis because a. nitrogenous bases have a net positive charge. b. nitrogenous bases have a net negative charge. c. phosphate groups have a net positive charge. d. phosphate groups have a net negative charge. e. None of the choices is correct.

D

DNA is denatured at a. 37oC. b. 42oC. c. 60oC. d. 94oC. e. 100oC.

D

In recombinant DNA technique, what enzyme is needed to seal the sticky ends of genes into plasmids or chromosomes? a. DNA polymerase I b. DNA polymerase II c. DNA helices d. DNA ligase e. primase

D

Protozoan classification is based on their means of: A. reproduction. B. growth. C. fermentation. D. locomotion. E. obtaining nutrients.

D

Semiconservative replication refers to a. each base bonding at the 1' position of the sugar. b. a purine always bonding to a pyrimidine. c. one helix strand that runs from the 5' to 3' direction and the other strand runs from the 3' to 5' direction. d. an original parent DNA strand and one newly synthesized DNA strand comprising a new DNA molecule. e. None of the choices is correct.

D

Split genes a. are common in bacteria and eukaryotes. b. only have exons initially transcribed to mRNA. c. have introns located only at the beginning and end of a coding region. d. use spliceosomes to excise introns and then join exons. e. All of the choices are correct.

D

Strain differences are helpful in: A. transduction. B. electrophoresis. C. replica plating. D. tracing the source of outbreaks of disease. E. transformation.

D

Strong chemical mutagens may be used to treat cancer cells. Is this a good idea or a bad idea? A. It is a bad idea; the cancer cells are already mutated and it is undesirable to mutate them further and make them more cancerous. B. It is a bad idea; the mutagens will also affect the non-cancerous cells, possibly leading to new cancerous states. C. It is a good idea; cancer cells must be killed as quickly as possible to cure the patient. D. The idea is both good and bad; the mutagens are very good at killing cancer cells but depending upon the mode of administration, they could also be a danger to non-cancerous cells.

D

The development of virulent, toxin-producing bacterial strains due to the presence of a temperate phage can occur in a. bacterial conjugation. b. transformation. c. generalized transduction. d. specialized transduction. e. All of the choices are correct.

D

The expression of genetic traits is the a. genome. b. genotype. c. proteome. d. phenotype. e. proteotype.

D

The terms yeast, mold, and mushrooms refers to fungal: A. reproduction. B. parasites. C. nutrition. D. morphology. E. biochemistry.

D

Which change in a gene's DNA sequence would likely have the least effect on the eventual amino acid sequence produced from it? A. Substitution of 1 nucleotide B. Addition of 1 nucleotide C. Deletion of 2 consecutive nucleotides D. Addition/deletion of 3 consecutive nucleotides E. Substitution of 1 nucleotide AND addition of 1 nucelotide

D

Which is TRUE about the RNA transcript? A. The template starts at the promoter region. B. It is formed using the DNA minus strand as a template. C. It has the same 5'-3' orientation as the DNA positive strand. D. It is formed using the DNA minus strand as a template, it has the same 5'-3' orientation as the DNA positive strand AND the template starts at the promoter region. E. It is made in short fragments that are then stitched together.

D

Which of the following is not true about mismatch repair? A. It utilizes the state of methylation of the DNA to differentiate between strands. B. It requires DNA polymerase and DNA ligase. C. It utilizes an endonuclease. D. It removes both strands in the mismatch area.

D

Serological methods: A. are useful in identifying unknown bacteria. B. rely on the specificity of an antibody-antigen interaction. C. may be simple and rapid. D. use cellular proteins and carbohydrates as markers. E. All choices are correct.

D - NOT B - I've seen others say B, it's not, got it wrong with B. I got nervous and changed my answer.

It has been estimated that most of the intestinal bacteria are A) Facultative anaerobes B) Facultative aerobes C) Obligate aerobes D) Obligate anaerobes

D) Obligate anaerobes

A researcher noted in a bacterium that there were more mutations in stretches of DNA having higher proportions of thymine than the other bases. Which is the most probable explanation for this observation? A) Thymine is easily converted to uracil by mutagens. B) The other bases are not prone to mutation. C) Thymine mutations cannot be repaired by the SOS system. D) Thymine dimers are more likely to form in those stretches. E) Most mutagens do not alter thymine.

D) Thymine dimers are more likely to form in those stretches.

Most bacteria, as well as all fungi and protozoa, are A) chemolithtrophs B) photoautotrophs C) photoheterotrophs D) chemoheterotrophs E) chemoautotrophs

D) chemoheterotrophs "Chemoheterotroph" is the term for an organism which derives its energy from chemicals, and needs to consume other organisms in order to live. - people are chemoheterotrophs. - Animals, most bacteria, fungi, and protozoa are chemoheterotrophs.

Which of the following statements regarding fungi is FALSE? A-Fungi reproduce by forming asexual or sexual spores. B-Most fungi grow well in acidic culture condition. C-Fungi tolerate low moisture conditions. D-Most fungi are pathogenic for humans. E-Fungi are eukaryotic heterotrophs.

D-Most fungi are pathogenic for humans.

In the malaria parasite life cycle, humans are the ________ host, while mosquitoes are the ________ host as well as the vector. A-vector, intermediate B-intermediate, intermediate C-temporary, final D-intermediate, definitive E-definitive, intermediate

D-intermediate, definitive The parasite which causes malaria (called Plasmodium) requires two different hosts—a vertebrate intermediate host, such as a human, and an insect definitive host, also known as the vector. For the types of malaria which infect humans and other mammals, the vector is always a mosquito of the genus Anopheles.

Which of the rRNA molecules has proven the most useful in taxonomy/identification? A. 70S B. 23S C. 80S D. 16S E. 5S

D. 16S

Serological methods A. are useful in identifying unknown bacterium. B. rely on the specificity of an antibody-antigen interaction. C. may be simple and rapid. D. All of the choices are correct.

D. All of the choices are correct.

In 1970 Stanier proposed that classification be based on A. evolution. B. Gram stain. C. physiology. D. DNA sequence.

D. DNA sequence.

E. coli is a Gram-negative bacillus that is found as intestinal normal microbiota. Which of the following would not be useful for an initial step in identifying E. coli O157:H7 strains in a stool sample? A. Growth on selective media, because all strains of E. coli will have the same metabolic capabilities. B. Serology, because E. coli strains all express the same antigens. C. RFLPs, because E. coli strains will be identical at the genome level. D. Gram staining, because E. coli strains will appear identical using this approach. E. These methods can all be used to differentiate between E. coli strains.

D. Gram staining, because E. coli strains will appear identical using this approach.

A breath test assaying for radioactive carbon dioxide may be used to indicate the presence of :

D. Helicobacter pylori.

Gram-positive encapsulated diplococci found in sputum are likely: A. Bacillus cereus. B. Pseudomonas aeruginosa. C. Escherichia coli. D. Streptococcus pneumoniae. E. Neisseria gonorrhea.

D. Streptococcus pneumoniae. (C and D are G-)

Photoheterotrophs (energy source + carbon source)

D. Uses light energy and uses organic compounds

Purple nonsulfur bacteria (energy source + carbon source)

D. Uses light energy and uses organic compounds

Very often clinically relevant information may be obtained by examining: A. the sequence of proteins. B. the size and shape of the organism. C. the transformation ability. D. a wet mount AND the size and shape of the organism. E. a wet mount.

D. a wet mount AND the size and shape of the organism.

Chemoorganotrophs A. may use substrate-level phosphorylation to produce ATP. B. may use oxidative phosphorylation to produce ATP. C. utilize an electrochemical gradient. D. all of the above are true

D. all of the above are true

Methanogens often grow in association with: A. nitrifying bacteria. B. lithotrophic bacteria. C. photosynthetic bacteria. D. fermentative bacteria.

D. fermentative bacteria. (someone else said: chemoorganotrophs)

Phage typing: A. is used to extract DNA from cells. B. is used to distinguish bacterial strains AND is dependent on the type of eukaryotic cell. C. is dependent on the type of eukaryotic cell. D. is used to distinguish bacterial strains. E. is useful for determining eukaryotic cell types.

D. is used to distinguish bacterial strains.

The relatedness of organisms determined by counting common characteristics is called A. evolutionary taxonomy. B. amino acid sequences. C. DNA sequences. D. numerical taxonomy. E. suggests the organisms are very closely related at the species level AND means the GC content is 45%.

D. numerical taxonomy.

Comparatively greater energy is released when A. carbon dioxide is the final electron acceptor. B. hydrogen is the final electron acceptor. C. nitrate is the final electron acceptor. D. oxygen is the final electron acceptor.

D. oxygen is the final electron acceptor.

You are working in a clinical lab. Two E. coli samples are sent to you for analysis and you are asked to determined whether they are the same strain. You perform an antibiogram and find that the two samples exhibit the same sensitivity to the antibiotics you use in the procedure. This indicates: A. the organisms are the same strains but they will react differently in serology tests. B. the organisms are likely different strains but you need to confirm this with other methods. C. the two organisms are not likely to be susceptible to the same bacteriophages. D. the organisms are likely the same strain but you need to confirm this with other methods. E. the two organisms will show different results if they are Gram stained.

D. the organisms are likely the same strain but you need to confirm this with other methods

In E. coli O157:H7, the O157:H7 refers to the A. specific type of DNA present. B. specific genus. C. general family. D. the specific LPS and flagella type present

D. the specific LPS and flagella type present

If the GC content of two organisms is 45% in both, D. they may or may not be related.

D. they may or may not be related. - similarity doesn't mean relatedness - if the ratio deviates by more than a few %, organisms are not related.

Media that change color as a result of the biochemical activity of growing bacteria: A. usually require the addition of various reagents before the color is evident. B. contain a colorless reagent that breaks down. C. usually contain blood. D. usually contain a pH indicator. E. are always selective media.

D. usually contain a pH indicator.

Which tasks must a bacterial cell accomplish in order to multiply? Mitosis, gene expression, apoptosis DNA replication, mitosis, cytokinesis Replication, translation, protein synthesis DNA duplication, RNA synthesis, protein synthesis Protein synthesis, mitosis, capsule formation

DNA duplication, RNA synthesis, protein synthesis

PCR produces DNA fragments of a particular size. DNA fragments of all possible sizes. DNA fragments that are one nucleotide larger than the next fragment. DNA fragments that are three nucleotides smaller than the previous fragment. protein fragments of all possible sizes.

DNA fragments of a particular size.

The molecule(s) that act as molecular glue to bind DNA fragments together is/are DNAse. ligandase. DNA ligase. DNAse AND ligandase. Polymerase.

DNA ligase.

The nucleocapsid is composed of: - nucleic acid in the ribosome. - DNA or RNA, lipid, and protein. - protein located in the nucleus. - DNA and RNA and protein. - DNA or RNA, and protein.

DNA or RNA, and protein. - a virus will never have DNA AND RNA, it's either or.

The polymerase chain reaction is used to duplicate small sections of RNA. proteins. DNA. lipids. Lipopolysaccharides.

DNA.

DNA is characterized by which of the following feature(s)? - single-stranded - deoxyribose - ribose - thymine - Deoxyribose and thymine

Deoxyribose and thymine

How can some bacteria sense the density of cells in an environment? Measuring the depletion of oxygen in the environment. Sensing the depletion of water in the environment. Detecting the accumulation of endospores. Quantifying the accumulation of waste products. Detecting the concentration of a signaling molecule.

Detecting the concentration of a signaling molecule.

The group of Fungi in which sexual reproduction has not been observed is: Deuteromycetes has been further classified using:

Deuteromycetes. rRNA analysis

DNA transfer by conjugation is more efficient in a liquid medium setting, subjected to very mild agitation (stirring), rather than on an agar plate format. Why?

Direct cell-to-cell contact is required for this process and this is more likely to be achieved in the liquid format than on an agar plate (esp for relatively non-motile types of bacteria)

Possessing the entire sequence of a particular human genome may not be as useful as we think. Why not? The amount of "junk DNA" present in the human genome masks any useful genetic information that we'd like to obtain. Due to the presence of introns/exons, and pre-transcriptional modification, the protein profile varies considerably among people, so it would be better to determine that. Every human genome is different enough that knowing ONE human's DNA sequence can't tell us almost anything about ALL humans. It's not the DNA sequence that matters—we need to know the mRNA sequence of the human genome. Due to the presence of introns/exons, and splicing of RNA after transcription, the DNA sequence doesn't necessarily tell us the exact number/type of proteins that will eventually be made from it.

Due to the presence of introns/exons, and splicing of RNA after transcription, the DNA sequence doesn't necessarily tell us the exact number/type of proteins that will eventually be made from it.

A mutation that changes a normal codon to a stop codon is called a a. point mutation. b. silent mutation. c. back mutation. d. missense mutation. e. nonsense mutation.

E

Among the microorganisms, various genomes can include a. chromosomes. b. plasmids. c. mitochondrial DNA. d. chloroplast DNA. e. All of the choices are correct.

E

An ideal vector A. may be a plasmid or bacteriophage. B. has multiple restriction enzyme recognition sites. C. contains an origin of replication. D. contains a selectable marker. E. All of the choices are correct.

E

Analysis of DNA fragments in gel electrophoresis involves a. larger fragments that move slowly and remain closer to the wells. b. DNA that has an overall negative charge and moves to the positive pole. c. DNA fragments that are stained to see them. d. an electric current through the gel that causes DNA fragments to migrate. e. All of the choices are correct.

E

Common vectors used to transfer a piece of DNA into a cloning host are a. plasmids. b. viruses. c. bacteriophages. d. artificial chromosomes. e. All of the choices are correct.

E

DNA Polymerase III a. synthesizes primer. b. removes primer. c. joins Okazaki fragments. d. unzips the DNA helix. e. adds new bases and proofreads new DNA.

E

Eukaryotic chromosomes differ from bacterial chromosomes because only eukaryotes have a. histone proteins. b. chromosomes in a nucleus. c. several to many chromosomes. d. elongated, not circular, chromosomes. e. All of the choices are correct.

E

Fungal diseases are generally referred to as: A. systemics. B. infections. C. infestations. D. polymorphic. E. mycoses.

E

In order to get around the lack of ability of prokaryotes to remove introns from precursor RNA, it may be necessary to A. use different promoters. B. use the DNA after it has been processed. C. use the DNA directly. D. use the DNA directly AND use the DNA after it has been processed. E. turn mRNA into cDNA.

E

Luminescence A. is catalyzed by luciferase. B. may be controlled by quorum sensing. C. may be produced by bacteria. D. is triggered by high bacterial density. E. All of the choices are correct

E

PCR is particularly useful in A. detecting viable yet non-culturable organisms. B. assessing impure (multiple types of bacteria present) samples. C. dealing with very small numbers of bacteria. D. relatively quickly producing results. E. All of the choices are correct.

E

RNA molecules differ from DNA a. molecules because only RNA b. has ribose. c. has uracil. d. is typically one strand of nucleotides. does not have thymine. e. All of the choices are correct.

E

RNA molecules differ from DNA molecules because only RNA a. has ribose. b. has uracil. c. is typically one strand of nucleotides. d. does not have thymine. e. All of the choices are correct.

E

Swarmer cells are: A. Characteristic of Pseudomonas aeruginosa. B. formed by Myxobacteria. C.part of the green nonsulfur bacteria. D. also known as coliforms. E. formed by sheathed bacteria.

E

The site where the old DNA strands separate and new DNA strands will be synthesized is called the a. primer. b. Okazaki fragment. c. template. d. rolling circle. e. replication fork.

E

Which of the following is incorrect about transfer RNA? a. It has a bottom hairpin loop with an anticodon. b. An anticodon is complementary to a codon. c. It contains a binding site for an amino acid. d. The initiator tRNA that binds to the P site has the anticodon UAC. e. The initiator tRNA in bacteria carries tryptophan.

E

Which of the following is not true of an organism's genotype? a. is inherited b. are structural genes coding for proteins c. are genes coding for RNA d. are regulatory genes controlling gene expression e. are the expressed traits governed by the genes

E

Why is it a good idea for a bacterial cell to be able to utilize glucose FIRST as an energy source (until it is used up), THEN switch to lactose? A. Glucose provides 10 times as much energy when broken down as lactose B. Glucose is an easier compound to break down and obtain energy from than lactose C. Lactose cannot be used by bacterial cells as an energy source D. It's about conservation of energy; bacteria will not expand the energy to make the extra enzymes for breaking down lactose if glucose is available and the extra breakdown enzymes are not needed E. Glucose is an easier compound to break down and obtain energy from than lactose AND it's about conservation of energy-why expend the energy to make the extra enzymes for breaking down lactose when glucose is right there and doesn't need extra enzymes for breakdown

E

The Ames test is useful as a rapid screening test to identify those compounds that: A. will respond to chemical agents. B. will respond to chemical agents AND will protect an organism from cancer. C. will protect an organism from cancer. D. respond to the deletion of DNAses. E.have a high probability of being carcinogenic.

E - Ames test is about identifying if a chemical is a mutagen. Some can become carcinogenic in the body when they come into contact with animal enzymes so rat liver extract is added to check. E is the only one in that ball park or that made any sense.

DNA is characterized by which of the following feature(s)? A. Thymine. B. Ribose. C. Single-stranded. D. Deoxyribose. E. Deoxyribose AND Thymine.

E - DNA - ds, deoxyribose sugar, thymine - RNA - ss, ribose sugar, uracil, no thymine

Endospores: A. are a form of sexual reproduction. B. are involved in anaerobic respiration. C. are a dominant form of a bacterium. D. are formed by members of medically relevant groups of fungi. E.are a dormant form of a bacterium formed by members of medically relevant groups of bacteria.

E - Genus Bacillus and Clostridium - dormant form and Clostridium is responsible for many medical issues like botulism, gangrene, tetnus. Also, not fungi - are BACTERIA.

The specific sequence of nucleotides in the DNA to which the RNA polymerase binds is the: A.sigma region. B.signal sequence. C.core region. D.regulatory region. E.promoter region.

E - RNA polymerase binds to the promoter on DNA for transcription. It is upstream of the operator that a repressor can bind to/release to regulate transcription.

Planar molecules used as chemical mutagens are called: A. nitrous oxides. B. alkylating agents. C. base analogs. D. intercalating agents.

E - example is ethidium bromide that is used in gel electrophoresis - It is used because upon binding of the molecule to the DNA and illumination with a UV light source, the DNA banding pattern can be visualized. - alkylating agents are the most common chemical mutagens.

Coliforms: A. are an informal grouping of enterics. B. ferment lactose. C. includes E. coli. D. are used as indicators of fecal contamination. E. All of the choices are correct.

E - the enterics are FERMENTORS.

Movement of spirochetes occurs by means of structures called: A. cilia. B. flagella. C. pili. D. pseudopods. E. axial filaments.

E - also called endoflagella - Any of a series of flagella, wound around spirochetes, that form an axial filament.

In anaerobic respiration, all of the following molecules can be used as final electron acceptors except A) SO4- B) NO3- C) H2O D) NO2- E) O2

E) O2

The term phototroph refers to an organism that A) Obtains energy by oxidizing chemical compounds B) Uses CO2 for its carbon C) Does not need a carbon source D) Must obtain organic compounds for its carbon needs E) Obtains energy from sunlight

E) Obtains energy from sunlight

Which of the following statements about viruses is FALSE? A) Viruses contain a protein coat. B) Viruses use the anabolic machinery of the cell. C) Viruses have genes. D) Viruses contain DNA or RNA but never both. E) Viruses use their own catabolic enzymes.

E) Viruses use their own catabolic enzymes.

A viroid is a(n) A) complete, infectious virus particle. B) capsid without nucleic acid. C) infectious protein. D) provirus. E) infectious piece of RNA without a capsid.

E) infectious piece of RNA without a capsid. - viroid = RNA only Complete, infectious (extracellular) virus particle = Virion Infectious protein = Prion Provirus = a virus genome that is integrated into the DNA of a host cell. Talking about a bacteriophage? It's called a prophage.

The type of photosynthesis that does not produce oxygen A) Does not require sunlight B) Does not require CO2 as a reactant C) Occurs in algae and plants D) Occurs in cyanobacteria E)Occurs in certain bacteria

E)Occurs in certain bacteria

Fatty acid analysis A. can be used to identify Gram-negative bacteria. B. can be used to identify Gram-positive bacteria. C. uses gas chromatography to analyze fatty acid methyl esters. D. requires that cells be grown under standardized conditions. E. All of the above

E. All of the above

Members of the Archaea typically thrive in conditions of excessive A. heat. B. acidity. C. alkalinity. D. salinity. E. All of the choices are correct.

E. All of the choices are correct.

PCR is particularly useful in A. detecting viable yet non-culturable organisms. B. assessing impure (multiple types of bacteria present) samples. C. dealing with very small numbers of bacteria. D. relatively quickly producing results. E. All of the choices are correct.

E. All of the choices are correct.

Serological methods A. are useful in identifying unknown bacterium. B. rely on the specificity of an antibody-antigen interaction. C. may be simple and rapid. D. use cellular proteins and carbohydrates as markers E. All of the choices are correct.

E. All of the choices are correct.

Which technique(s) is/are used to help identify and classify bacteria? A. microscopic examination B. culture characteristics C. biochemical tests D. nucleic acid analysis E. All of the choices are correct.

E. All of the choices are correct.

Wisconsin state health authorities alerted the CDC about an E. coli O157:H7 outbreak. Soon thereafter, officials from two other states reported that they also had cases of illness associated with this pathogen. Within days, the CDC determined that the E. coli strains from all three states were the same, and the likely source of the outbreak was a particular brand of pre-packaged fresh spinach. The CDC then issued a press release advising people not to eat bagged fresh spinach. Which of the following is NOT a method used to differentiate E. coli O157:H7 from other strains based directly on genotype? A. Radioisotope-labeled probes or fluorescent dye-labeled probes B. Fluorescence in situ hybridization (FISH) C. 16S rRNA gene sequencing D. Nucleic acid amplification tests (NAATs) E. Matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS)

E. Matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS)

Which organism(s) is/are acid-fast? A. Nocardia B. Pseudomonas C. E. coli D. Mycobacterium E. Nocardia AND Mycobacterium

E. Nocardia AND Mycobacterium

Organisms that grow very slowly, cannot be cultured, are present in very small numbers, or are mixed with a number of other bacteria may still be identified using: A. replica plating. B. the Ames test. C. positive selection. D. Southern blotting. E. PCR. F. Escherichia coli.

E. PCR.

Approximately 99% of the microbes in the intestines are obligate anaerobes. We have plenty of blood vessels that can bring oxygen to the tissues of the intestines. Why would there be obligate anaerobes within these areas? A. The aerobic microbes are outcompeted for nutrients in these areas by the anaerobic microbes. B. The inside space of the intestines is highly anaerobic. It is deep inside the body where carbon dioxide accumulates. C. The bacteria consume all the oxygen in the tissue areas brought by the blood vessels, creating an anaerobic environment. D. The bacteria in the intestines are protected from exposure to the oxygen in the tissues by the lining of the intestines. E. The inside space of the intestines is highly anaerobic. It is deep inside the body where oxygen cannot reach and it is not supplied with blood.

E. The inside space of the intestines, [where bacteria reside], is highly anaerobic. It is deep inside the body where oxygen cannot reach AND, [unlike the surrounding tissues], it is not supplied with blood.

In a MALDI-TOF assay, A. part of a colony is transferred to a microscope slide, and a drop of hydrogen peroxide (H2O2) is added to it to test for catalase. B. the nucleotide sequence of ribosomal RNA molecules (rRNAs), or the DNA that encodes them (rDNAs), is used to identify microbes. C. specimens are inoculated onto differential media and a set of biochemical tests are used to identify a microorganism. D. antibodies are used to detect specific proteins and polysaccharides, particularly those that make up surface structures. E. a microorganism's proteins are separated and sorted by mass to generate a profile that provides a fast way to identify a colony.

E. a microorganism's proteins are separated and sorted by mass to generate a profile that provides a fast way to identify a colony.

An ideal vector: A. may be a plasmid or bacteriophage B. has multiple restriction enzyme recognition sites C. contains an origin of replication D. contains a selectable marker E. all of the choices are correct

E. all of the choices are correct

A selective growth medium: A. accentuates differences between the growing bacteria. B. allows no bacteria to grow. C. allows all bacteria to grow. D. is cultured anaerobically. E. allows only certain bacteria to grow.

E. allows only certain bacteria to grow.

Wolbachia are found only in: A. plants. B. marine water. C. hot springs. D. mammals. E. arthropods.

E. arthropods - like insects, spiders and mites

Which of the following is NOT true about laboratory strains of E. coli being desirable hosts for genetic engineering? E. coli has known phenotypic characteristics. E. coli is fastidious but can usually be grown in the lab. The genetics of E. coli is very well known. E. coli is especially able to express foreign genes. All of the answer choices are correct.

E. coli is fastidious but can usually be grown in the lab.

Which of the following is an example of phase variation? E. coli producing pili for attachment to epithelial cells. S. pyogenes producing a capsule of hyaluronic acid, which is also a host component. N. gonorrhoeae expressing different types of pilin protein. Influenza virus expressing variations of glycoprotein HA and NA spikes. These are all examples of phase variation.

E. coli producing pili for attachment to epithelial cells.

The gene for human insulin has been successfully cloned in human cells. pig cells. rhinovirus. S. aureus. E. coli.

E. coli.

Sequencing of rRNA is useful for A. determining evolutionary relationships. B. determining protein sequences. C. identification of unknown bacteria. D. serological relationships. E. determining evolutionary relationships AND identification of unknown bacteria.

E. determining evolutionary relationships AND identification of unknown bacteria.

Phycobiliproteins are A. found in purple sulfur bacteria. B. found in cyanobacteria. C. used to gather wavelengths of light that are not well absorbed by chlorophyll. D. are used to reduce hydrogen sulfide. E. found in cyanobacteria AND used to gather wavelengths of light that are not well absorbed by chlorophyll.

E. found in cyanobacteria AND used to gather wavelengths of light that are not well absorbed by chlorophyll.

You examine a patient who is complaining of belching (burping), bloating, and some vomiting. She also has some abdominal discomfort which she describes as a dull, burning pain that is worse when she is hungry and is often relieved when she takes antacids. You suspect that she may have Helicobacter pylori gastritis, and send her for a urea breath test. The breath test is positive; based on this, you get the patient's stool tested for blood, and you send her for an endoscopy, during which a biopsy is taken. Your diagnosis is confirmed by the results of these tests and that she does indeed have H. pylori. Your patient asks you to explain how the urea breath test works. You tell her that in the test, she had been asked to swallow urea containing an unusual form of carbon—non-radioactive 13C (an isotope). After 10-30 minutes, she was asked to breathe into a receptacle, and her breath had been analyzed for the presence of this form of carbon in the carbon dioxide that she exhaled. You explain that the CO2 she exhaled contained 13C, so: A. her test indicates that her stomach cells used the 13C-containing urea in cellular respiration, producing glucose and releasing CO2 containing 13C as a byproduct. B. her test indicates the presence of H. pylori—the organism contains 13C in its cell wall, and in the presence of stomach acid, the cell wall is broken down to release CO2 containing 13C which could be measured. C. her test indicates the presence of H. pylori—the organism produces ammoniase that breaks down the 13C-containing urea that the patient swallowed into urea and CO2 containing 13C which could be measured. D. nobody really understands how the urea breath test works, but that it is well known that anybody who drinks urea containing 13C and exhales CO2 containing this element afterwards needs treatment for an ulcer. E. her test indicates the presence of H. pylori—the organism produces urease that breaks down the 13C-containing urea that the patient swallowed into ammonia and CO2 containing 13C which could be measured.

E. her test indicates the presence of H. pylori—the organism produces urease that breaks down the 13C-containing urea that the patient swallowed into ammonia and CO2 containing 13C which could be measured.

Phenotypically identical bacteria A. look the same. B. are genetically exactly the same. C. may be told apart by DNA sequence analysis. D. may not be told apart by any means. E. look the same AND may be told apart by DNA sequence analysis.

E. look the same AND may be told apart by DNA sequence analysis.

Various strains of E. coli: A. may be harmless. B. are all exactly the same. C. are all very different from one another. D. may cause disease. E. may cause disease AND may be harmless.

E. may cause disease AND may be harmless.

Why were the slime molds and water molds once considered to be fungi? - They have the same material in their cell walls (chitin) that fungi possess. - Early identification methods focused on appearances rather than genetic similarities/differences. - Early identification methods focused on appearances rather than biochemical characteristics. - Water molds and slime molds are STILL considered to be fungi. - Water molds and slime molds always occur in the same habitats as fungi.

Early identification methods focused on appearances rather than genetic similarities/differences.

_________ are a dormant form of a bacterium formed by members of medically relevant groups of bacteria

Endospores

Which of the following structures would be the best choice as a biological indicator to test autoclave operations? - Cysts formed by Azotobacter species. - Dormant spores in the conidia of Streptomyces species. - Microcysts within the fruiting bodies of myxobacteria. - Sulfur granules produced by Thiothrix species. - Endospores formed by Geobacillus stearothermophilus.

Endospores formed by Geobacillus stearothermophilus.

If you read that coliforms had been found in a lake, the repot could have been referring to which of the following genera?

Escherichia

Why would it be more difficult to treat diseases in humans caused by members of the Eukarya than diseases caused by the Bacteria?- - Eukaryotic microbes (unlike prokaryotes) often secrete compounds that breakdown and eliminate drugs used against them. This makes them much harder to effectively eliminate than bacteria. - Multicellular organisms always have their own immune systems for protection, so any treatment we develop needs to overcome this built-in protection mechanism. - Since bacteria are so much simpler (being single-celled) than multi-cellular eukaryotic microbes, they are naturally easier to kill off. - Eukaryotic pathogens multiply much more effectively in a human host than bacterial pathogens do; they attain extremely high numbers in the host, making it very difficult to get rid of them. - Eukaryotic microbes use many of the same enzymes and systems as humans, so we lose the ability to target certain molecules that might be present ONLY in the cell type we want to eliminate.

Eukaryotic microbes use many of the same enzymes and systems as humans, so we lose the ability to target certain molecules that might be present ONLY in the cell type we want to eliminate.

T/F - Anoxygenic phototrophs grow photosynthetically only under aerobic conditions.

FALSE

A codon consists of two nucleotides. T/F

False

Algae have a vascular system very similar to that found in plants, true or false?

False

Double-stranded DNA enters the recipient cell during transformation. True False

False

Organisms termed his- are considered prototrophic for histidine. True False

False

PCR typically results in the generation of fragments of all sizes. T/F

False

Protozoans are eukaryotes and as such will always possess a nucleus, mitochondria, and chloroplasts, true or false?

False

T/F - Fungi are often capable of locomotion through the use of flagella.

False

T/F - If each of two bacteria have a GC content of 50%, they are both definitely closely related.

False

T/F - Slime molds and water molds are types of fungi.

False

T/F - Streptococcus pyogenes can be easily distinguished microscopically from other Streptococcus species.

False

T/F Generalized transduction involves the transfer of phage genes from one bacterial cell to another.

False

T/F Generalized transduction is so called because specific bacterial genes are transferred during this process.

False

T/F: Strains of an organism can always reliably be identified using RFLPs (restriction fragment length polymorphisms).

False

TRUE OR FALSE: Completed filamentous phages are often found in the cytoplasm of infected bacteria.

False

The Ames test determines antibiotic sensitivity of a bacterium. True False

False

Your niece has been diagnosed with Diamond-Blackfan anemia, an extremely rare disorder of the bone marrow that causes people have a low red blood cell (RBC) count. The disease is classified as a ribosomal protein disease, meaning that one or more of the genes involved in ribosome production is/are mutated, and the ribosomes are not synthesized properly. Although it is not currently understood why mutations in ribosome biosynthesis affect blood cell formation particularly, you are able to help your sister understand the role of ribosomes in the cell and the consequence of ribosome failure, so that she has a better grasp of her child's condition. One of the genes affected in Diamond-Blackfan Anemia is called RPS19. This gene plays a role in maturation of the 40S subunit. Your sister tells you she heard that protein synthesis can occur normally if the large ribosomal subunit is present, even if the small subunit is not because the large subunit is the part that decodes the information. You tell her that this is T/F

False

T/F - Obligate aerobes may transform energy via fermentation.

False - THEY NEED O2, it's the terminal e- acceptor

T/F - Algae may directly infect humans and cause disease.

False - indirectly - toxins

T/F - Lactic acid bacteria such as Streptococcus are obligate fermenters that can exist in an aerobic environment due to their use of catalase to mitigate the presence of oxygen.

False - obligate fermenters = aerotolerant anaerobes that don't notice of oxygen is even present. Don't make catalase. - catalase breaks down the ROS hydrogen peroxide into water and oxygen

T/F - Serratia marcescens are red when incubated at 37°C.

False. - red at 22°C.

T/F Numerical taxonomy uses a battery of genotypic characteristics to classify bacteria.

False. It uses comparison of a lot of phenotypic traits.

If the name given ends in -aceae, it's a ________________ name but if it ends in -ales it is a(n) _________________ name.

Family, Order

What is the number of tRNA molecules that may be associated with translation? Fewer than 64 Fewer than 20 64 2 20

Fewer than 64

Diatoms are algae whose silicon dioxide-containing shells are useful economically as: 1. Fertilizers 2. Filters 3. Stabilizers 4. Agar 5. Thickeners

Filters

Which are not arthropods? - Mosquitoes - Flukes - Lice - Fleas - Ticks

Flukes - flukes (trematodes) are helminths (parasitic worms) - arthropods are insects and arachnids

The genomes of free-living spirochetes are larger than those living in animal hosts. Why might this be so? A.Parasitic spirochetes are smaller than free-living spirochetes. Because of this, their genomes are also smaller; they need less genes. B. It isn't so—all spirochetes would have the same size genomes, since they're all the same species of microbe. C. A smaller genome implies simplicity—the spirochetes living in animal hosts have fewer needs, so they need fewer genes. D. The spirochetes in animal hosts are different species entirely. As different species, they would naturally have smaller genomes. E. Free-living spirochetes will need genes for additional proteins to synthesize or obtain their own food from the environment. Parasitic spirochetes obtain nutrients from the animal host.

Free-living spirochetes will need genes for additional proteins to synthesize or obtain their own food from the environment. Parasitic spirochetes obtain nutrients from the animal host.

This group includes unicellular as well as filamentous forms, a number of which cause infections. Members of this group produce a variety of different reproductive spores and filaments referred to as hyphae.

Fungi

Which may be or is an RNA molecule? GGGCCCA and GCCCUUA GGGCCCA and AAATTTA AGCCTAC and GGUCCCU AGCCTAC and GGGCCCA GCCCUUA and AAATTTA

GGGCCCA and GCCCUUA

Which of the following are diseases caused by protozoa? 1. Schistosomiasis, amebiasis, AND primary amebic meningoencephalitis. 2. Dengue fever, malaria, AND plague. 3. Amebiasis, malaria, AND plague. 4. Giardiasis, malaria, AND toxoplasmosis. 5. Giardiasis, malaria, AND trichinellosis.

Giardiasis, malaria, AND toxoplasmosis.

Why is it a good idea for a bacterial cell to be able to utilize glucose FIRST as an energy source (until it is used up), THEN switch to lactose?

Glucose is an easier compound to break down and obtain energy from AND Conservation of energy: it takes more energy to make extra enzymes to break down lactose.

Why is it a good idea for a bacterial cell to be able to use glucose FIRST as an energy source (until it is depleted), THEN switch to lactose? Glucose is an easier compound to break down and obtain energy from than lactose AND for conservation of energy: why use the energy to make the enzymes for breaking down lactose when glucose doesn't need any extra enzymes for breakdown? Glucose provides 10x as much energy when broken down as lactose AND for conservation of energy: why use the energy to make the enzymes for breaking down lactose when glucose doesn't need any extra enzymes for breakdown? For conservation of energy: why use the energy to make the enzymes for breaking down lactose when glucose doesn't need any extra enzymes for breakdown AND because breakdown of lactose produces inhibitory compounds. For conservation of energy: why use the energy to make the enzymes for breaking down lactose when glucose doesn't need any extra enzymes for breakdown AND because lactose always triggers endospore formation, which may be unnecessary. Lactose can only be used by a small number of bacteria as an energy source AND for conservation of energy: why use the energy to make the enzymes for breaking down lactose when glucose doesn't need any extra enzymes for breakdown?

Glucose is an easier compound to break down and obtain energy from than lactose AND for conservation of energy: why use the energy to make the enzymes for breaking down lactose when glucose doesn't need any extra enzymes for breakdown?

Paralytic shellfish poisoning occurs when humans eat shellfish that have fed on: - Vibrio cholerae. - Salmonella species. - Volvox species. - E. coli. - Gonyaulax species.

Gonyaulax species.

Why are viroids resistant to nucleases? - Viroids have only been identified in plants. Plant nucleases cannot digest RNA. - Nucleases will only digest DNA, not RNA, so viroids are protected. - Having a circular RNA "genome," with no protein shell, they are resistant to the protein-degrading activities of nucleases. - Viroids are composed of single stranded RNA; nucleases only act on double-stranded molecules. - Having a circular RNA "genome," they are resistant to most exonucleases (that digest the free ends of RNA or DNA).

Having a circular RNA "genome," they are resistant to the digestion of most exonucleases (that nibble/digest the free ends of RNA or DNA).

Members of this group come in flat or round forms, and although many parasitize animals, there are also free-living forms. Parasitic members of this group often have complex life cycles involving one or more intermediate hosts in which larvae develop.

Helminths

Which is the CORRECT definition of PCR? Procedure in which a fragment of DNA is inserted into a vector and then transferred into another cell, where it then replicates. In vitro technique used to repeatedly duplicate (amplify) a specific region of a DNA molecule, increasing the number of copies exponentially. The process in which two complementary strands of DNA from different sources are annealed to create a hybrid double-stranded molecule. Use of the enzyme reverse transcriptase to generate cDNA from mRNA, and then amplifying the cDNA exponentially using RNA polymerase. In vitro process of determining the nucleotide sequence of a DNA molecule using a variety of enzymes.

In vitro technique used to repeatedly duplicate (amplify) a specific region of a DNA molecule, increasing the number of copies exponentially.

How does Ascaris lumbricoides, an intestinal parasite, cause choking and pulmonary symptoms in some people? - Ingested Ascaris larvae penetrate intestinal capillaries, from where they are carried to the lungs, causing coughing and shortness of breath. - Ascaris is a pulmonary parasite; it only enters the intestine of people with other lung conditions, including asthma. - Ascaris larvae are highly allergenic; when they are ingested, they cause an allergic reaction which includes coughing. - People inadvertently inhale Ascaris worms when they bring contaminated food close to their mouths; these cause pulmonary blockages. - Ascaris, being anaerobic, form large cysts in pulmonary tissue; these accumulate in the lungs, causing coughing.

Ingested Ascaris larvae penetrate intestinal capillaries, from where they are carried to the lungs, causing coughing and shortness of breath.

Most temperate phages integrate into the host chromosome, whereas some replicate as plasmids. Which kind of relationship do you think would be more likely to maintain the phage in the host cell, and why? - Integration, because plasmids are frequently lost during cell division, which could leave a daughter cell without the virus genome. - Plasmids; they're smaller, so they would be easier to replicate by the host cell. - Integrated; the host cell would be less likely to view this DNA as "foreign" on subsequent rounds of replication, and would retain it more easily. - Plasmids; these structures often carry other genes that may give the host cell a selective advantage over cells that don't have them. - Either plasmids or integration because once a virus genome is in a host cell, there is not way for that genome to be removed from the infected cell.

Integration, because plasmids are frequently lost during cell division, which could leave a daughter cell without the virus genome.

Which is NOT true of RNA? It functions in the cytoplasm. It contains ribose. It is usually single-stranded. It contains both uracil and thymine. It is a component of ribosomes.

It contains both uracil and thymine.

To maximize the number of thymine dimer mutations following UV exposure, should you keep a plate of fungal cells in the dark, in the light, or does it matter at all?

It does not matter; fungal cells do not possess the enzymes needed for photorepair of thymine dimers because these enzymes are found only in prokaryotes

Does the presence of introns/exons in eukaryotic cells provide more potential diversity in gene products (proteins) than is possible in prokaryotic cells? It doesn't. There is the same potential for gene products (proteins) in a bacterium with 1,000 genes as there is in a eukaryotic cell with 1,000 genes. It does. Exons/introns can be spliced together in different ways post-transcription to yield different mRNAs (and therefore, different proteins). Bacteria lack this system. It does. Each exon and each intron could be used individually and discretely to make a gene product (protein). Since bacteria lack these, they will have less ability to create different proteins. It does. Exons/introns can be spliced together in different ways at the DNA level to eventually yield different mRNAs (and therefore, different proteins). Bacteria lack this system. It doesn't. Bacteria and eukaryotes have the same number of introns and exons, and can thus synthesize the same types and numbers of proteins.

It does. Exons/introns can be spliced together in different ways post-transcription to yield different mRNAs (and therefore, different proteins). Bacteria lack this system.

Why is the position of the first AUG after the ribosome binding site critical? It establishes the reading frame. It initiates transcription. Every polypeptide must start with arginine. Every polypeptide must start with methionine. Every polypeptide must end with methionine.

It establishes the reading frame

Which is FALSE about the RNA transcript? It is made in short fragments that are then stitched together. It is formed using the DNA minus strand as a template. The template starts at the promoter region. It has the same 5'-3' orientation as the DNA positive strand. All the answers are false.

It is made in short fragments that are then stitched together.

Which of the following about DNA microarray technology is NOT true? It relies on visual detection of the labeled probes after hybridization. It involves the use of fluorescently labeled singe-stranded cDNA. It uses nucleic acid hybridization. It may use many DNA fragments that function like probes. It involves attaching nucleotides to a solid support such as a glass slide.

It relies on visual detection of the labeled probes after hybridization.

Which is not true about mismatch repair? It utilizes an endonuclease. It requires DNA polymerase and DNA ligase. It utilizes the state of methylation of the DNA to differentiate between strands. It removes both strands in the mismatch area.

It removes both strands in the mismatch area.

Which of the following microbes is (are) important to cheese-making?

LACTIC ACID BACTERIA & PROPINONIBACTERIUM

Which of the following colonize the vagina during childbearing years? - Enterobacter - Lactobacilli - Clostridium - Clostridium AND lactobacilli - Streptococci

Lactobacilli

Thermoplasma and Picrophilus grow best in which of the following extreme conditions?

Low pH and high temperature

How would increased travel lead to increased spread of multicellular eukaryotic parasites? - Many eukaryotic parasites depend on vectors (often small blood-sucking insects) for transmission, so moving an infected individual into an area with new vectors and new susceptible humans would increase spread. - It really would NOT; most individuals are screened for parasitic infections prior to traveling out of highly infected areas. We also have quarantine abilities at customs stations for individuals entering the United States. - Eukaryotic parasites are too small to travel great distances effectively; by hitching a ride on luggage, clothing, fruit/vegetables, and other food products, they can enter new geographic areas. - Traveling generally weakens a person's immune system, making them vulnerable to parasitic eukaryotes in any new place that they visit. - Many eukaryotic parasites are transmitted directly from person to person via airborne transmission, so getting an infected individual onto a plane of susceptible individuals would increase spread.

Many eukaryotic parasites depend on vectors (often small blood-sucking insects) for transmission, so moving an infected individual into an area with new vectors and new susceptible humans would increase spread.

Please select the definition that is INCORRECT. - Mycobacteria—Gram-negative bacteria that group together to form complex fruiting bodies. - Chemolithotrophs—organisms that harvest energy by oxidizing inorganic chemicals. - Anoxygenic phototrophs—photosynthetic organisms that do not produce O2. - Chemotrophs—organisms that obtain energy by oxidizing chemical compounds. - Nitrifiers—Gram-negative bacteria that obtain energy by oxidizing inorganic nitrogen compounds.

Mycobacteria—Gram-negative bacteria that group together to form complex fruiting bodies.

The Gram-positive rod that is also acid-fast and is a human pathogen is

Mycobacterium tuberculosis.

The amino acid that is placed first during translation in bacteria, mitochondria, and chloroplasts is the promoter. N-formyl-glycine. methionine. N-formyl-methionine. Glycine.

N-formyl-methionine.

Cells are often ground up with abrasive to get to their internal enzymes/molecules, followed by removal of the abrasives. Here are three situations and three outcomes. What is the correct interpretation of the results? In situation #1, radioactive amino acids are added to cell material, and radioactive proteins are produced. In situation #2, radioactive amino acids, cell material, and the enzyme DNAse (degrades DNA) are added together. Radioactive proteins are still produced. In situation #3, the ground-up cell material is allowed to sit for 24 hours before radioactive amino acids and DNAse are added to it. No radioactive protein is produced. What is the most likely interpretation? RNA polymerase has no activity after 24 hours, so no mRNA is transcribed and translated into radioactive proteins in the last scenario. No conclusions can be made from the information given. More results are needed to interpret these experiments. The radioactivity in the amino acids is altering/degrading the tRNA molecules, leading to no protein production in the last scenario. Natural RNAses present in the ground-up material will degrade any existing mRNAs in that 24-hour interval. Added DNAses break down DNA so that new RNAs are not synthesized. This will lead to a loss of capability to translate protein in the last scenario. The radioactivity in the amino acids completely disappears within 24 hours. Transcription and translation occur as usual, but there is no radioactivity left in the system, so proteins are untagged.

Natural RNAses present in the ground-up material will degrade any existing mRNAs in that 24-hour interval. Added DNAses break down DNA so that new RNAs are not synthesized. This will lead to a loss of capability to translate protein in the last scenario.

The conversion of ammonium to nitrate could be accomplished by the presence of: - Nitrosomonas, Nitrobacter, and Anabaena. - Nitrosomonas and Nitrobacter. - Anabaena alone. - Nitrosomonas alone. - Nitrobacter alone.

Nitrosomonas and Nitrobacter.

Which of the following statements is true about the relationship between natural selection and mutation? A) Natural selection creates mutations. B) Mutations assist natural selection. C) Mutations produce natural selection. D) Natural selection does not rely on mutations. E) None of the above are true.

No answer - I think it's B.

Which of the following best explains why Bruce Ames added a rat liver step to his mutagen testing? A) It better modeled how carcinogens act in the body. B) The rat liver extracts increased the mutation rate in the bacteria. C) Rat liver cells detected the mutagens. D) The rat liver produces histidine. E) None of the above are correct.

No answer but I think it's A. - add rat liver to the Ames test so see if a suspected mutagen becomes a problem when in the presence of bodily enzymes.

Would ID50 and LD50 necessarily be the same for a given virus? Why or why not?

No, because a virus may be highly infectious (very low ID50 value) but only marginally lethal (very high LD50 value), for example the rhinovirus (common cold virus).

An antibiotic is added to a culture of E. coli, resulting in death of the cells. Bacteriophages are then added. Would the phages replicate in the E. coli cells? Why or why not? - No, because the bacteriophages would depend too much on having the active machinery of a living host cell for replication. - Yes, because bacteriophages are capable of reanimating dead cells to force them to produce more virus particles. - No, because dead E. coli cells do not have any receptors on their cell walls to which the bacteriophages can attach for entry into the host cell by fusion. - Yes, because the cellular machinery of the bacteria is most likely still active. The bacteriophages could use that machinery to replicate new virus particles. - No, because entry of the bacteriophages into the target cell is dependent on the cell being alive to conduct endocytosis of the virus.

No, because the bacteriophages would depend too much on having the active machinery of a living host cell for replication.

polymerase chain reaction (PCR) can be used to perform DNA sequencing reactions. In this case, are 2 primers (a forward and a reverse) necessary?

No; dideoxynucleotide sequencing depends on different length fragments being formed and then separated based on size and this can take place with only a specific forward primer OR a specific reverse primer

A student complains that it makes no sense to worry about coliform bacteria in water, since we naturally possess harmless coliforms in our intestines anyway. Why do regulatory agencies worry about coliform bacteria in water supplies then?

Not all coliforms are harmless and symbiotic with humans; it is best to keep coliforms out of the water since it is difficult to identify which are harmless and which are harmful.

Polymerase chain reaction (PCR) can be used to perform DNA sequencing reactions. In this case, are two primers (a forward and a reverse) necessary? No—you actually need a primer pair for each round of DNA amplification ... so you'll need many, many primer pairs, depending how many rounds you plan to do. Yes—if you only have one primer, you will only be able to determine the dideoxynucleotide sequence of RNA, which is a single-stranded molecule. Yes—and it will be important to make sure that the primer pairs are made with dideoxynucleotides that are labeled with fluorescent dyes. Otherwise, you won't be able to detect the fragments that are made in the PCR process. Yes—you can't perform PCR without two specific primers to amplify the region in question in the DNA. No—dideoxynucleotide sequencing depends on different length fragments being formed and then separated based on size. This can take place with only a specific forward OR a specific reverse primer.

No—dideoxynucleotide sequencing depends on different length fragments being formed and then separated based on size. This can take place with only a specific forward OR a specific reverse primer.

Are all fungi detrimental (bad) for other organisms?

No—it depends on the fungus and the relationship it has with the other organism. Some fungi can form a symbiotic relationship with plant roots that increases their nutrient and water absorption. This is good.

Would you expect the number of virions to be the same if you measured them by the plaque assay or by counting using the electron microscope? Why? - Yes—both methods measure the total number of virus particles in a solution. - Yes—only fully functioning viruses will be released from a host cell, so the quantified number of virus particles in a plaque assay should be identical to the number of free virus particles counted by electron microscopy. - No—the plaque assay only measures viable virus particles, while the electron microscope cannot distinguish between defective and viable virus. - No—you cannot count virus particles by using a plaque assay. You can only get a relative difference in quantity from one preparation of virus particles to another with this method.

No—the plaque assay only measures viable virus particles, while the electron microscope cannot distinguish between defective and viable virus.

Which of the following is/are true of DNA replication? Nucleotides are added to the 3' end. It starts at the origin of duplication. It is carried out by transcriptases. It requires a DNA primer to get started. All of the choices are true.

Nucleotides are added to the 3' end.

Burst size

Number of phage particles released -for T4 phages, it is around 200

Identify the statement about digestion of DNA by restriction enzymes that is NOT true. It generates restriction fragments. It produces blunt ends. It produces sticky ends. One strand of the DNA molecule is cut. All of the answer choices are correct.

One strand of the DNA molecule is cut.

You are sent three clinical samples and are asked to determine whether they are the same strain. You perform standard identification techniques but cannot come to a conclusion. You decide to do an RFLP test. You digest the genomes of the organisms with the same restriction enzyme and run a gel. Each organism yields 5 bands on the gel, of the following sizes: Organism A: 3 kb, 7 kb, 11 kb; 14 kb, 21 kb; Organism B: 3 kb, 7 kb, 2 kb, 8 kb, 11 kb; Organism C: 11 kb, 3 kb, 14 kb, 7 kb; 21 kb What conclusion(s) can you make from this result?

Organisms A and C are likely the same strain but are different from organism B.

Organisms that grow very slowly, are non-culturable, are present in very small numbers, or are mixed with a number of bacteria may still be identified using

PCR

Most enveloped viruses, like hepatitis B, are released by budding, a process whereby the virus acquires its envelope. Before budding occurs, virally encoded protein spikes insert into specific regions of the host cell's membrane. Given this information, which of the following would you tell your friend best describes the structure of the viral envelope? A. Phospholipid bilayer with host-derived proteins. B. Phospholipid bilayer C. Phospholipid bilayer studded with both virus- and host-derived proteins. D. Phospholipid monolayer studded with virus- and host-derived proteins. E. Protein layer with host-derived spikes.

Phospholipid bilayer studded with both virus- and host-derived proteins.

You and your exercise buddy decide to go to Yosemite National Park to hike the famous El Capitan trail. You book your trip through a well known agency but before you leave for your vacation, you learn that there have been two cases of plague reported in people who recently visited a different area of the park. Your friend is anxious and tells you he thinks that plague is really dangerous and kills people everyone who gets it. He points out that this disease killed a lot of people during the Middle Ages, and says he doesn't want to do the trip after all. You decide to do some research on the plague and its causative agent before making a decision about your trip. Please select the FALSE statement regarding plague and its transmission. - People can contract plague when they are bitten by fleas from rodents infected with the causative organism. - Y. pestis is typically transmitted by the bites of infected fleas, an example of biological transmission. Plague is caused by a Gram-negative organism and is thus completely untreatable with antibiotics. - Yersinia pestis is a Gram-negative organism and thus possess an outer lipopolysaccharide layer. - The incidence of vector-borne diseases such as plague can be decreased by controlling the vector or the infected hosts.

Plague is caused by a Gram-negative organism and is thus completely untreatable with antibiotics. - you can use antibiotics on G-. - The three main antimicrobial agents recommended to treat plague are streptomycin, tetracycline, and chloramphenicol (1). Streptomycin remains the drug of choice. See? - is a Gram-negative, nonmotile, rod-shaped, coccobacillus bacteria, with no spores. It is a facultative anaerobic organism that can infect humans via the Oriental rat flea. It causes the disease plague, which takes three main forms: pneumonic, septicemic and bubonic plagues.

a "spell check" function by the normal replication enzyme to ensure fidelity

Proofreading

What part of the E. coli T4 phage attaches to the host cell receptors?

Protein fibers at the end of the phage tail.

Members of this group cause malaria and diarrheal illnesses such as amebiasis and giardiasis. Many members of this group are motile by means of cilia, flagella, or pseudopods

Protozoa

RNA is characterized by which one of the following features? Deoxyribose Thymine Double-stranded Ribose All of the answer choices are correct.

Ribose

How could heavily fertilized lawns contribute to cyanobacterial blooms in lakes and oceans? -Large amounts of fertilizer will lead to excessive production of greenhouse gases (like CO2) from grass in lawns. Excessive CO2 production will lead to large blooms of cyanobacteria in water systems. -They won't—the two systems are completely unrelated. How could grass in lawns contribute to effects in lakes and oceans? -Nutrient-rich grass will be mowed down, with grass clipping bits eventually washing into sewer systems and into larger bodies of water. These grass clippings will serve as a nutrient source for cyanobacteria, leading to blooms. -Run-off from the lawns will get into the water system, leading to large amounts of nitrogen that can be used by cyanobacteria in water systems. - Fertilizers contains compounds that encourage the production of bacteriochlorophylls; after rain, fertilizers get into water and are used by cyanobacteria.

Run-off from the lawns will get into the water system, leading to large amounts of nitrogen that can be used by cyanobacteria in water systems. Cyanobacteria are PROKARYOTES

catastrophic DNA damage caused by UV light can be survived by the cell with this

SOS repair

Which of the following definitions is CORRECT? - Zooplankton—microscopic free-floating photosynthetic organisms. - Saprophytes—organisms that take in nutrients from dead and decaying matter. Proglottids—short, non-segmented, bilaterally symmetrical flatworms. Kinetoplastids—a group of protozoa that penetrate host cells by means of a structure called an apical complex. Mycelium—thread-like structure that characterizes the growth of most fungi and some bacterial species.

Saprophytes—organisms that take in nutrients from dead and decaying matter. - zoo = animal - flatworms (Platyhelminthes) - proglottids are the tapeworm segments with both male and female reproductive structures. - Apicomplexans have the apical complex. - the threadlike structures are filaments and a visible mass of them is the mycellium.

An early attempt by Cohn at bacterial classification grouped bacteria according to their A. biochemistry. B. Gram stain. C. shape. D. arrangement.

Shape

Agarose gel electrophoresis separates nucleic acid fragments according to Size. shape. nucleobase sequence. type of 5C sugar. Density.

Size.

Please select the INCORRECT statement regarding helminths and the diseases they cause. - Sometime helminth eggs are ingested on the surface of contaminated foods. For example, pinworm eggs (Enterobius vermicularis) may be transmitted a food surface. - Some helminths are inadvertently ingested. For example, Onchocerca volvulus, the cause of River blindness, is transmitted by drinking contaminated water or eating fish carrying this parasite. - Some helminths are inadvertently eaten with food. For example, eating undercooked pork containing Trichinella spiralis larvae is the most common cause of trichinellosis. - Some helminths burrow into people. For example, immature forms of hookworm larvae live in the soil and can burrow through human skin. - Some helminths are transmitted through insect bites. For example, Wuchereria bancrofti, the cause of elephantiasis, is transmitted by mosquitoes.

Some helminths are inadvertently ingested. For example, Onchocerca volvulus, the cause of River blindness, is transmitted by drinking contaminated water or eating fish carrying this parasite. - it is transmitted by black flies

Which pair is INCORRECT? Okazaki fragments—generated on the lagging strand during DNA replication. Signal transduction—transmission of information from outside a cell to inside the cell. Constitutive enzymes—enzymes that are constantly produced by a cell. Promoter—nucleotide sequence to which RNA polymerase binds to start transcription. Splicing—removal of introns from prokaryote mRNA following transcription.

Splicing—removal of introns from prokaryote mRNA following transcription.

Which of the following is NOT associated with a Clostridium species? - Botulism - Antibiotic-associated diarrheal disease - Gas gangrene - Strep throat - Tetanus

Strep throat

A catalase-negative colony growing on a plate that was incubated aerobically could be which of the following genera?

Streptococcus

The name Lactococcus (streptococcus) lactis indicates that

Streptococcus is the old genus name

True or False: F plasmids and oftentimes R plasmids are both able to code for production of a pilus

T

The sequence of cDNA synthesized from an mRNA template with the sequence AUGGUA would be ________. This cDNA probe would hybridize to gene chip DNA with the sequence ________. UACCAU; ATGGTA AUGGUA; AUGGUA AUGGUA; TACCAT TACCAT; AUGGUA TACCAT; ATGGTA

TACCAT; ATGGTA

T/F - Bacteria and Archaea both have members that use sulfur compounds as a terminal electron acceptor.

TRUE

T/F - Endospores of Bacillus stearothermophilus are used in testing autoclave operation.

TRUE

T/F - The most medically relevant species of Pseudomonas is P. aeruginosa.

TRUE

Cells are often ground up with abrasive to get to their internal enzymes/molecules, followed by removal of the abrasives. Here are two situations and two outcomes. What is the correct interpretation of the results? In situation #1, radioactive amino acids are mixed with ground-up cell material. Radioactive proteins are produced. In situation #2, radioactive amino acids AND the enzyme RNAse (an enzyme that degrades RNA) are mixed with ground-up cell material. No radioactive proteins are produced. The results cannot be interpreted—there isn't enough information given in the question. The mRNA from the cell can be used to make proteins with the radioactive amino acids in the first situation. In the second situation, the mRNA is destroyed by the RNAse before it can be translated into protein containing the radioactive amino acids. The DNA from the cell can be translated into protein using the radioactive amino acids in the first situation. The RNAse in the second situation degrades the ribosomal RNA (rRNA), preventing ribosomes from forming and making proteins with the radioactive amino acids. The radioactivity in the amino acids corrupts the tRNA molecules, leading to no protein production in the second scenario. The radioactivity in the medium causes the DNA of the bacteria to mutate. This causes a malfunction of all the enzymes of that cell.

The mRNA from the cell can be used to make proteins with the radioactive amino acids in the first situation. In the second situation, the mRNA is destroyed by the RNAse before it can be translated into protein containing the radioactive amino acids.

You are graduating from nursing school in three months and have already lined up a new job. However, your employer informs you that before you start your job, it is mandatory for you to be vaccinated against hepatitis B, a double-stranded DNA virus that can cause the disease hepatitis. Your boyfriend, a biology major, wonders why you need to get the vaccine. You aced your microbiology class and you know a lot about both viruses and vaccines, so you understand why getting this vaccination is essential. You give your boyfriend a mini lesson on this by answering a few of his questions. You tell your friend that you are happy to be receiving your vaccination because hepatitis B is associated with hepatocellular carcinoma (liver cancer). Select the FALSE statement regarding viruses and cancer. - Viruses that lead to cancer formation are called oncogenic viruses. - Viruses that insert their genome into the host cell's chromosome may cause changes at the insertion site, converting a proto-oncogene into an oncogene. - Some viruses carry an oncogene—infection with these viruses interferes with the host cell's own growth-control mechanisms. - The majority of tumors are caused by oncogenic viruses but some may be caused by mutations in host genes that regulate cell growth. - The most common viral causes of tumors are certain DNA viruses such as hepatitis B virus.

The majority of tumors are caused by oncogenic viruses but some may be caused by mutations in host genes that regulate cell growth. - pg 351 says "the majority of tumors are not caused by oncogenic viruses, however, but by mutations in host genes that regulate cell growth."

Sarcoptes scabiei

The mite that causes scabies in humans and mange in dogs.

In a recent research article describing the use of FISH to detect LNTB, the authors noted that they used probes that were only 20 base pairs (bp) in length rather than the conventional 100 bp—500 bp. Given what you know about acid-fast bacteria, why do you think they took this approach? The nature of the Mycobacterial cell wall likely makes is difficult for larger probes to enter the cell. Mycobacteria have a lipopolysaccharide outer membrane through which larger probes cannot enter. The nature of the Mycobacterial cytoplasmic membrane likely makes is difficult for larger probes to enter the cell. Mycobacteria have smaller ribosomes than any other bacteria and the probes are targeted at rRNA. The nature of the Mycobacterial capsule likely makes is difficult for larger probes to enter the cell.

The nature of the Mycobacterial cell wall likely makes is difficult for larger probes to enter the cell.

When DNA probes are used to identify bacterial DNA similarities by hybridization, the probe DNA is heated and the template DNA is treated to separate the two strands. Why would the probe DNA be heated?

The probe DNA is single-stranded but it may have folded back on itself and formed portions that are double-stranded; heating it up breaks up any possible hydrogen bonds that may have formed, returning it to a single-stranded state prior to hybridization

When DNA probes are used to identify bacterial DNA similarities by hybridization, the probe DNA is heated and the template DNA is treated to separate the 2 strands. Why would the probe DNA be heated?

The probe DNA is single-stranded, but it may have folded back on itself and formed portions that are double-stranded. Heating it up breaks any possible hydrogen bonds that may have formed, returning it to a single-stranded state prior to hybridization.

What distinguishes Staphylococcus, species from Streptococcus, Enterococcus and Lactococcus species? - Their morphology. - The production of catalase. - The nature of their cell walls. - Their ability to cause disease. - All of these.

The production of catalase.

You make two agar plates: one is a nutrient agar plate (plate A) that contains histidine and penicillin. The other is a glucose salts agar (plate B) that also contains penicillin. You inoculate a sample onto both plates using replica plating technique, incubate the plates, and compare the growth after 48 hours. There are 12 colonies on the nutrient agar plate and 11 colonies on the glucose salts medium. Which of the following statements is INCORRECT? - Prototrophs and auxotrophs in this experiment are resistant to penicillin. - Approximately 92% of the bacteria in the original sample are prototrophs. - The colony that is missing from plate B is an auxotroph that cannot synthesize histidine. - This experiment describes indirect selection of a mutant. - The prototrophs are resistant to penicillin but the auxotrophs are sensitive to this antibiotic.

The prototrophs are resistant to penicillin but the auxotrophs are sensitive to this antibiotic.

Sexually transmitted human papillomavirus (HPV) strains are among the most common of the sexually transmitted infection (STI) agents. Some HPV strains (low risk) cause papillomas—warty growths of the external and internal genitalia. Other strains (high risk) cause lesions of mucosal surfaces and are more problematic—approximately 15 of these strains are strongly associated with cancer of the cervix, penis, rectum, vagina, or throat. These high-risk strains include HPVs 16, 18, 31, and 45. You have been asked to give a short presentation on HPV and its detection by PCR (the HPV test). Following your presentation, you answer questions from your audience. PCR generates a DNA fragment of a distinct size even when the whole viral chromosome is used as a template. What determines the boundaries of the amplified fragment? The length of time of the elongation step in each cycle. The sites on the template DNA to which the specific primers used in the reaction anneal. The temperature at which the elongation step in each cycle is carried out. The position of a termination sequence, which causes the Taq polymerase to fall off the template. The concentration of one particular deoxynucleotide in the reaction.

The sites on the template DNA to which the specific primers used in the reaction anneal.

A researcher discovered a mutation in bacteria that causes rapid degradation of the bacterial DNA. Which of the following provides the best explanation of the mutation? A) Restriction enzyme function was hindered by the mutation. B) The mutation increased DNA methylation. C) Methylation of the bacterial DNA was decreased by the mutation. D) The mutation disabled SOS repair. E) Thymine dimers were not repaired as a result of the mutation.

There was no answer but I think it's C. Why? Unmethylated isn't seen as self and is destroyed by restriction enzymes.

Some arthropods cause disease even when they do not act as a vector. Which of the following is an example of this? - Dust mites do not transmit infectious disease, but inhalation of the mites and their waste products can sometimes trigger asthma. - The larvae of some mites are called "chiggers" and may cause intense itching where they attach and feed on fluids within skin cells. - Scabies is characterized by an itchy rash caused by allergic reactions to female mites that have burrowed into the outer layers of skin. - The pubic louse is commonly transmitted during sexual intercourse and can cause an unpleasant itch associated with "crabs." - These are all examples of the situation described.

These are all examples of the situation described.

What are the characteristics of Lactic acid bacteria such as Streptococci?

They are obligate fermentors.

Which statement about aflatoxins is NOT true? They are possible carcinogens. They are produced by Aspergillus. They are toxins. They are produced by Candida. They may be found in peanuts.

They are produced by Candida.

Which of the following statements regarding tapeworms is FALSE? - They absorb nutrients from the host's gut through their skin. - A single worm contains broth male and female reproductive organs. - They do not have a digestive system. - They complete their life cycle in a single host. - They can sometimes cause neurological signs and symptoms in the host.

They complete their life cycle in a single host. -tapeworms don't have a complete digestive system because they latch on and absorb nutrients from the host's gut through their SKIN - the SCOLEX is the head with suckers or hooklets, attached by the neck to PROSTIGLIDS that have both male and female reproductive parts so that as the worm elongates the segments farther way are full of fertilized eggs that come off and get pooped out. - they can sometimes cause neurological signs and symptoms in the host and no, they don't live their whole lives in one host - some use fleas, rabbits, deer, sheep, etc for their INTERMEDIATE HOST

Which statement about most phages that contain single-stranded DNA is NOT true? - Their DNA is transformed to dsDNA before replication and transcription occur. - They are extruded from the host cell. - They contain a negative-sense DNA strand. - All of the choices are correct. - None of the choices is correct.

They contain a negative-sense DNA strand - filamentous phases are ssDNA - fig 13.8 shows it being ss(+)DNA

Which of the statements BEST describes tapeworms? - They may be transmitted by eating undercooked meat. - They do not have a digestive system AND they may be transmitted by eating undercooked meat. - They have a complicated digestive system. - They have a complicated digestive system AND they may be transmitted by eating undercooked meat. - They do not have a digestive system.

They do not have a digestive system AND they may be transmitted by eating undercooked meat.

Which statement(s) about cells taken from a tumor is/are true? a) They may be used to grow bacteriophages. b) They divide 50 times and then die AND they may be used to grow bacteriophages. c) They divide 50 times and then die. d) They may be used to grow viruses AND they may be used to grow bacteriophages. e) They may be used to grow viruses.

They may be used to grow viruses.

How do anoxygenic phototrophs benefit from having accessory pigments that allow light to be harvested at deeper areas of a moist or aquatic environment? - This allows even anaerobic microbes to conduct photosynthesis, as they can harvest light energy in the deeper areas where oxygen won't be present, use wavelengths of light not absorbed by the photosynthetic organisms closer to the surface of the water; AND don't have to compete with other cells that use oxygen in the upper levels for the scarce nutrients in the fluid environment. - These organisms don't have to compete with other cells that use oxygen in the upper levels for the scarce nutrients in the aquatic environment. - Accessory pigments allows even anaerobic microbes to carry out photosynthesis, as they can harvest light energy in the deeper areas where oxygen won't be present. - The cells can use wavelengths of light that have not been absorbed by the photosynthetic organisms closer to the surface of the water. - This allows even anaerobic microbes to conduct photosynthesis, as they can harvest light energy in the deeper areas where oxygen won't be present AND can use wavelengths of light not absorbed by the photosynthetic organisms closer to the surface of the fluid.

This allows even anaerobic microbes to conduct photosynthesis, as they can harvest light energy in the deeper areas where oxygen won't be present, use wavelengths of light not absorbed by the photosynthetic organisms closer to the surface of the water; AND don't have to compete with other cells that use oxygen in the upper levels for the scarce nutrients in the fluid environment.

When a tissue sample such as lymph node tissue is to be analyzed by FISH, it must first be treated with chemicals. Which of the following is NOT a reason that this step is needed? To make the cells more permeable so that the labeled probe can easily enter. To break down the cellulose walls of the tissue so that the probes can enter those cells. To maintain cell shape. To inactivate enzymes that might otherwise degrade the nucleic acid of the cells. To inactivate enzymes that might otherwise degrade the nucleic acid of the cells AND to maintain cell shape.

To break down the cellulose walls of the tissue so that the probes can enter those cells.

Which of the following is INCORRECT? Transcription is the process of copying mRNA from DNA. Binary fission is the process of bacterial cell division. Replication is the process of duplicating a DNA molecule. Transcription is the conversion of DNA into RNA. Translation is the process of synthesizing protein using information in mRNA.

Transcription is the conversion of DNA into RNA.

A very common vector is a plasmid. T/F

True

Antisense RNA is the complement of the plus strand and may be useful in inhibiting translation. T/F

True

Crown gall is caused by a prokaryote plasmid that can be expressed in plant cells. True False

True

DNA polymerase is able to proofread the DNA sequence. True False

True

DNA probes are used to find regions of complementary DNA. T/F

True

Each gene mutates at a characteristic frequency. True False

True

F plasmids and oftentimes R plasmids are both able to code for production of a pilus. True False

True

Most of the medically important multicellular parasites are arthropods or helminths, true or false?

True

Plasmids often carry the information for antibiotic resistance. True False

True

Ribozymes are non-protein molecules with catalytic activity. T/F

True

Scientists use CRISPR for gene editing. T/F

True

T/F - A probe is a single-stranded piece of nucleic acid labeled with a detectable marker, used to locate a unique nucleotide sequence that identifies a particular microbial species.

True

T/F - All known species of bacteria are described in Bergey's Manual of Systematic Bacteriology.

True

T/F - All viruses must separate the nucleic acid from the capsid before replication.

True

T/F - Based on DNA hybridization, humans and chimpanzees are the same species.

True

T/F - Chlamydia occurs in two forms, a reticulate body and an elementary body.

True

T/F - The host range of a virus depends on the presence of host receptor molecules.

True

T/F - The skin and oral cavity may have anaerobic microenvironments.

True

T/F - Virulent as well as temperate phages can serve as generalized transducing phages.

True

T/F - Viruses, viroids, and prions are obligate intracellular agents.

True

T/F - You isolate a prokaryote. After performing analysis on the organism, you cannot find a description matching that of your organism in the reference text Bergey's Manual of Systematic Bacteriology. This suggests that you have likely isolated a new organism.

True

T/F Horizontal DNA transfer may make it more difficult to construct phylogenetic trees.

True

T/F Size and shape may allow one to differentiate between a bacterium, fungus, or protozoan.

True

T/F Sometimes a piece of bacterial DNA near the specific site of insertion stays attached to the phage DNA, and a piece of phage DNA remains behind.

True

T/F The lambda phage DNA always integrates into the host DNA in the same specific site.

True

T/F: For prokaryotes, species is a group of closely related isolates or strains.

True

The genetic code is nearly universal. T/F

True

The minus strand of DNA serves as the template for RNA production. T/F

True

Transposons may leave a cell by incorporating themselves into a plasmid. True False

True

True or false: transduction often involves defective virus

True

Typically, arthropods serve as vectors of disease, while helminths directly cause disease, true or false?

True

rRNA sequence comparisons are useful for determining evolutionary relationships. T/F

True

true or false: the integration of phage DNA into host DNA occurs in much the same fashion as seen in transformation, transduction, or conjugation.

True

T/F - Rhizobium is considered an endosymbiont with plants.

True - specifically with root nodules of legumes where they fix nitrogen

A filamentous phage is incapable of causing a lytic infection.

True - they leave via extrusion

The formation of a covalent bond between two adjacent thymines is caused by mustard gas. alkylating agents. microwave radiation. UV radiation.

UV radiation

What would the outcome be if you forgot to do the washing step when carrying out FISH on a sample containing bacteria? Unbound probe would remain on the slide and would fluoresce, making it impossible to see individual cells. Nothing. Unbound probe will not fluoresce, so even if it is present, it will not affect the results. Nothing. The washing step is recommended but is not necessary and can be omitted. The unbound probe would anneal strongly to the glass slide in random patterns that would look like bacteria. The unbound probe would cause lysis of the target bacterial cells, destroying their nuclei and mitochondria.

Unbound probe would remain on the slide and would fluoresce, making it impossible to see individual cells.

How are target cells identified using the FISH technique? Using an electron microscope. Using a fluorescence microscope. Using DNA sequencing. Using DNA microarrays. By detecting UV levels.

Using a fluorescence microscope.

In the phototrophic production of energy, the oxygen originates from A. carbon dioxide. B. water. C. glucose.

Water

What metabolic process creates the rotten egg smell characteristic of many anaerobic environments?

When sulfur compounds are used as terminal electron acceptors, they become reduced to hydrogen sulfide (chemical responsible for smell)

Why would all protozoa be expected to require large amounts of water in their habitats? - They require water to help them during photosynthesis by providing an electron source. - Without being in water, they would quickly undergo plasmolysis (due to their small size) and die. - Without being in water, they would quickly dehydrate (due to their small size) and die. - They require water to move around in to seek food particles and would be unable to move without water. - None of the statements is correct.

Without being in water, they would quickly dehydrate (due to their small size) and die.

HPV is a DNA virus and can be detected in a sample using PCR. Is it possible to detect an RNA virus using this technique or something similar? No; there is no known process by which RNA can be copied because the subunits of RNA are amino acids and these cannot be amplified without the use of ribosomes. No; PCR can only be carried out on a double-stranded molecule such as DNA, and RNA is a single-stranded molecule. Yes; a variation of PCR is RT-PCR in which an enzyme called reverse transcriptase generates cDNA from mRNA in a sample, and that cDNA is then amplified exponentially. Yes; Taq polymerase is a unique DNA polymerase that can copy either RNA or DNA, so it doesn't matter what type of virus is present—the enzyme will still detect it in a PCR reaction. There is no answer to this question because nobody has ever tried to amplify RNA; viruses contain both DNA and RNA so it is always possible to detect the DNA component.

Yes; a variation of PCR is RT-PCR in which an enzyme called reverse transcriptase generates cDNA from mRNA in a sample, and that cDNA is then amplified exponentially.

The study of the crown gall tumor found a bacterial plasmid promoter that was similar to plant promoters. an R plasmid. incorporation of the bacterial chromosome into the plant. incorporation of the plant chromosome into the bacteria.

a bacterial plasmid promoter that was similar to plant promoters.

A lysogen is: - a temperate phage that can insert its DNA into the host's DNA. - a bacterium that carries phage DNA (a prophage) integrated into its genome. - an insect that carries virus DNA in its genome. - a bacteriophage that lyses its host as a result of its replication cycle. - a bacteriophage that carries bacterial DNA integrated into its genome.

a bacterium that carries phage DNA (a prophage) integrated into its genome.

For synthesis of an inducible enzyme to occur, a compound must bind to the operator. a product must bind to the terminator. a compound must bind to the repressor. a corepressor must bind to the start codon. lactose must be present without fructose.

a compound must bind to the repressor.

Coccidioidomycosis is: - a protozoan disease caused by Candida sp. - a viral disease caused by Coccidioides sp. - a protozoan disease caused by Coccidioides sp. - a fungal disease caused by Candida sp. - a fungal disease caused by Coccidioides sp.

a fungal disease caused by Coccidioides sp. - Valley Fever - The name and the myco- = fungal was the give away.

Macroscopic algae possess a special structure that acts as an anchor and is commonly called: 1. the stipe. 2. roots. 3. the bladder. 4. a thallus. 5. a holdfast.

a holdfast

Plague is caused by Yersinia pestis, a Gram-negative facultatively anaerobic rod. It is non-motile and grows best at 28°C. Because you are a microbiology student, you know that the organism is: - a mesophile that cannot grow when oxygen is present. - a mesophile that grows best in the presence of oxygen but can also grow without it. - a mesophile that grows best without oxygen but can also grow when oxygen is present. - a psychrophile that grows best in the presence of oxygen but can also grow without it. - a psychrophile that grows best without oxygen but can also grow when oxygen is present.

a mesophile that grows best in the presence of oxygen but can also grow without it.

The site at which a virus has infected and subsequently lysed the infected cell, releasing its progeny to infect and lyse surrounding cells, thereby forming a "clear zone," is: - a plaque. - a burst area. - a lyse area. - a dead zone. - a zone of inhibition.

a plague - they count these in plaque assays

Goal(s) of gene cloning may be to produce a protein. a protein, many copies of the gene to be used as a probe, AND many copies of the gene for sequencing. many copies of the gene to be used as a probe. more copies of the host cell. many copies of the gene for sequencing.

a protein, many copies of the gene to be used as a probe, AND many copies of the gene for sequencing.

Is antigenic shift alone likely to lead to influenza pandemics? a) Perhaps-but it would most likely be a mixture of antigenic shift AND drift that would result in a pandemic strain. b) No-antigenic SHIFT is responsible for changes in the hemagglutinin protein, while antigenic DRIFT is responsible for changes in the neuraminidase protein. You need both to lead to a pandemic strain. c) Yes-ONLY antigenic shift can lead to the large-scale mixing of gene elements required to produce a pandemic flu strain. d) No-ONLY antigenic DRIFT can lead to the large-scale mixing of gene elements required to produce a pandemic flu strain.

a) Perhaps-but it would most likely be a mixture of antigenic shift AND drift that would result in a pandemic strain.

Intercalating agents act during DNA synthesis. often result in frame shift mutations. only act in dormant cells. alter the hydrogen bonding properties of the bases. act during DNA synthesis AND often result in frame shift mutations.

act during DNA synthesis AND often result in frame shift mutations.

The agarose used in electrophoresis

acts as a sieve

Most fungi are: - obligate anaerobes. - microaerophiles. - photosynthetic. - aerobes or facultative anaerobes. - obligate aerobes.

aerobes or facultative anaerobes

Agar is obtained from: - protozoans. - bacteria. - plants. - algae. - yeasts.

algae

The largest group of chemical mutagens consists of radiation. base analogs. nitrous acid. alkylating agents.

alkylating agents

Coliforms - are an informal grouping of enterics - ferment lactose - includes E. coli - are used as indicators of fecal contamination - all of the above

all of the above

Luminescence - is catalyzed by luciferase - may be controlled by quorum sensing - may be produced by bacteria - is triggered by high bacterial density - all of the choices are correct

all of the choices are correct

Genetic engineering relies on recombinant DNA technology AND relies completely on conjugation. allows the use of bacteria as production factories for a number of molecules AND relies completely on conjugation. allows the use of bacteria as production factories for a number of molecules AND relies on recombinant DNA technology. allows the use of bacteria as production factories for a number of molecules AND is dependent on RNA enzymes. is dependent on RNA enzymes AND relies on recombinant DNA technology.

allows the use of bacteria as production factories for a number of molecules AND relies on recombinant DNA technology.

The polymerase chain reaction is used to amplify mRNA. amplify certain sections of DNA. produce long polymers of amino acids to be used in electrophoresis. produce long polymers of carbohydrates to be used in electrophoresis. produce proteins.

amplify certain sections of DNA.

In conjugation the donor cell is recognized by the presence of an F plasmid. a Y chromosome. diploid chromosomes. an SOS response. an F plasmid AND diploid chromosomes.

an F plasmid

_________ use hydrogen sulfide or organic compounds as a source of electrons.

anoxygenic phototrophs

Competent cells are able to take up naked DNA. are antibiotic resistant. occur naturally. can be created in the laboratory. are able to take up naked DNA, occur naturally AND can be created in the laboratory.

are able to take up naked DNA, occur naturally AND can be created in the laboratory.

Activators are involved in positive control AND bind to the terminator. are involved in negative control AND bind to the start codon. are allosteric proteins AND are involved in positive control are allosteric proteins AND are involved in negative control. are involved in negative control AND bind to the terminator.

are allosteric proteins AND are involved in positive control

Heterocysts: - are found in nitrogen-fixing cyanobacteria AND generate oxygen. - are used to protect nitrogenase AND generate oxygen. - are found in nitrogen-fixing cyanobacteria AND are used to protect nitrogenase. - produce catalase AND are found in nitrogen-fixing cyanobacteria. - are found in nitrogen-fixing cyanobacteria AND produce catalase.

are found in nitrogen-fixing cyanobacteria AND are used to protect nitrogenase. - made by Anabeana

Lysogenized cells : are immune to any further infection by any virus. are immune to infection by the same virus. may have new properties. respond to infection with the SOS response. are immune to infection by the same virus AND may have new properties.

are immune to infection by the same virus AND may have new properties.

The Ames test is useful as a rapid screening test to identify those compounds that will respond to chemical agents. are mutagens. respond to the deletion of DNases. will protect an organism from cancer. will respond to chemical agents AND will protect an organism from cancer.

are mutagens

The methanogens: - are part of the domain Archaea AND appear only in aerobic environments. - are part of the domain Archaea AND oxidize hydrogen gas to produce methane. - use oxygen as a terminal electron acceptor AND appear only in aerobic environments. - oxidize hydrogen gas to produce methane AND appear only in aerobic environments. - use oxygen as a terminal electron acceptor AND oxidize hydrogen gas to produce methane.

are part of the domain Archaea AND oxidize hydrogen gas to produce methane.

Pseudomonas

are resistant to many disinfectants and antimicrobials AND are mostly harmless except for the opportunistic P. aeruginosa.

Haustoria... 1. are specialized hyphae used by parasitic fungi. 2. are a form of parasitic protozoan. 3. are the reproductive form of protozoans. 4. are a type of root used by all climbing plants. 5. refers to the reproductive structure formed by slime molds.

are specialized hyphae used by parasitic fungi.

Treponema and Borrelia

are spirochaetes.

Insertion sequences are the simplest type of transposon. code for a transposase enzyme. are characterized by an inverted repeat. can produce pili. are the simplest type of transposon, code for a transposase enzyme AND are characterized by an inverted repeat.

are the simplest type of transposon, code for a transposase enzyme AND are characterized by an inverted repeat.

Dideoxynucleotides are useful in generating proteins AND act as chain terminators. are useful in nucleic acid sequencing AND have two additional hydroxyl groups at the 2' and 3' carbons. act as chain initiators AND are useful in nucleic acid sequencing. are useful in nucleic acid sequencing AND act as chain terminators. act as chain initiators AND have two additional hydroxyl groups at the 2' and 3' carbons.

are useful in nucleic acid sequencing AND act as chain terminators.

Mycorrhizae: - are vital for the survival of lichens AND are vital for the survival of many plants. - are vital for the survival of many plants AND are used in the production of wine, beer, and bread. - increase the absorptive ability of roots AND are used in the production of wine, beer, and bread. - are used in the production of wine, beer, and bread AND are vital for the survival of lichens. - are vital for the survival of many plants AND increase the absorptive ability of roots.

are vital for the survival of many plants AND increase the absorptive ability of roots.

Wolbachia are found only in

arthropods

Movement of spirochetes occurs by means of structures called

axial filaments

Which does not refer to the shape of a virus? - Helical - Icosahedral - Bacillus - Complex - These are all virus shapes.

bacillus

Chemical mutagens that mimic the naturally occurring bases are called nitrogen mustards. alkylating agents. base analogs. nitrous oxide.

base analogs

A particular characteristic of disease-causing Streptococcus is: - lactic acid production. - beta-hemolysis. - endospore formation. - growth at refrigerator temperatures. - catalase production.

beta-hemolysis

Yersinia pestis is transmitted by fleas. The organism forms biofilms in the digestive tract of infected fleas, often blocking the tract. This prevents the flea from feeding properly, causing bacteria to be regurgitated into the bite wound that the flea has made. In this situation, the flea is a: - dead-end host. - mechanical vector. - mechanical host. - biological vector. - biological host.

biological vector

The purple sulfur and green sulfur bacteria: - generate oxygen and lack gas vesicles. - generate oxygen. - preferentially use organic molecules as an electron source. - both use hydrogen sulfide as a source of electrons. - both lack gas vesicles.

both use hydrogen sulfide as a source of electrons.

Negative control means that a regulator molecule is

bound and transcription is inhibited AND removed and transcription begins

Negative control means a regulator molecule is bound, and transcription is inhibited. bound, and transcription is inhibited OR removed, and transcription starts. removed, and transcription is inhibited. bound, and transcription starts. removed, and transcription starts.

bound, and transcription is inhibited OR removed, and transcription starts.

In addition to lysis, animal viruses may exit the host cell by: - budding. - fusion. - endocytosis. - extrusion. - fission.

budding

The shape of the virus is determined by its: - envelope. - capsid. - spikes. - nucleic acid. - tail.

capsid - shapes are icosahedral, helical or complex. It's how the capsomeres are put together into the capsid. HInt: bacillus does not refer to the shape of a virus.

X-rays have no effect on DNA. cause thymine trimers. cause single and double strand breaks in DNA molecules. make the DNA radioactive.

cause single and double strand breaks in DNA molecules.

Phthirus pubis, 1. are transmitted by mosquitoes 2. cause "crabs" 3. Transmit bacterial disease 4. Infect the blood 5. Are biological vectors

causes "crabs"

Tuberculosis (TB) is caused by the acid-fast bacterium Mycobacterium tuberculosis. Although most TB cases affect the lungs (pulmonary TB), some infections occur in other body sites (extrapulmonary TB). Among these cases, lymph node tuberculosis (LNTB) is the most common. Diagnosis of LNTB by conventional methods (staining, biochemical tests) has limitations—for example, formaldehyde preservation of tissue biopsies interferes with the acid-fast stain, leading to underdiagnosis or misdiagnosis. Now fluorescent in situ hybridization (FISH) is being used to diagnose extrapulmonary TB. When detecting microorganisms, a probe that hybridizes to sequences on ribosomal RNA (rRNA) is generally used. This is because not all bacteria have DNA but they all have large quantities of ribosomal RNA. RNA is a single-stranded molecule but DNA is a triple helix and must be denatured. rRNA is in the cytoplasm so is easy to detect but DNA is in the nucleus so is harder to detect. cells that are dividing can have thousands of copies of rRNA, increasing the technique's sensitivity. These are all reasons that rRNA is targeted.

cells that are dividing can have thousands of copies of rRNA, increasing the technique's sensitivity.

Which of the following pairs is mismatched? - nematodes : complete digestive tract - cestodes : all are free-living - trematodes : flukes - nematodes : many are free-living - cestodes : segmented body made of proglottids

cestodes all are free-living - these are tapeworms.

All fungi have ______ in their cell walls.

chitin

All fungi have ________ in their cell walls. chitin cellulose peptidoglycan pectin ergesterol

chitin

The site in a photosynthetic eukaryotic cell where photosynthesis occurs is the: - carotenoid. - Golgi. - chloroplast. - nucleus. - mitochondria.

chloroplast.

Modern approaches to evolutionary taxonomy often involve:

comparison of DNA or RNA

The placement of the amino acid during translation is determined by the

complementarity of the codon-anticodon

A virion is a(n): - complete, extracellular virus particle. - pathogenic virus. - subviral particle. - non-enveloped virus particle. - enveloped virus particle.

complete, extracellular virus particle.

Gene transfer that requires cell-to-cell contact is transformation. competency. conjugation. functional genomics.

conjugation

The transfer of vancomycin resistance from Enterococcus faecalis to Staphylococcus aureus is thought to have involved conjugation. transformation. transduction. transposons. conjugation AND transposons.

conjugation AND transposons

Nitrous acid most frequently causes mutations by substituting oxygen for hydrogen bonds. converting keto groups to amino groups. altering the bonding ratios of nitrogen bases. converting cytosine to uracil.

converting cytosine to uracil

The changes that occur in virally infected cells are characteristic for a particular virus and are referred to as the: - genotypic expression. - cytology. - cytopathic effect. - symptomatic effect. - phenotypic effect.

cytopathic effect

A mutation in E. coli results in the loss of both restriction endonucleases and modification enzymes. Would you expect any difference in the frequency of gene transfer via transduction FROM Salmonella INTO this E. coli strain? a) Yes-the loss of the restriction endonucleases would leave the recipient E. coli unable to break down "invading"' viral DNA from the transducing phage. This would lead to higher rates of successful transduction. b) No-transduction efficiency isn't affected by either restriction endonucleases or modification enzymes, so there'd be no effect on the overall rate. c) No-since the Salmonella strain is normal, the rate of production of transducing virus particles would still be the same, resulting in the same frequency of gene transfer. d) Yes-the loss of the restriction endonucleases would leave the recipient E. coli unable to break down "invading" viral DNA from the transducing phage, AND the loss of the modification enzymes would leave the recipient E. coli unable to tag its own DNA as "self," leaving the viral DNA untagged and recognizable as "foreign," and targeted for destruction. Together, thesewould lead to higher rates of successful transduction. e) Yes-the loss of the modification enzymes would leave the recipient E. coli unable to tag its own DNA as "self," leaving the viral DNA untagged and recognizable as "foreign," and targeted for destruction. This would lead to higher rates of successful transduction.

d) Yes-the loss of the restriction endonucleases would leave the recipient E. coli unable to break down "invading" viral DNA from the transducing phage, AND the loss of the modification enzymes would leave the recipient E. coli unable to tag its own DNA as "self," leaving the viral DNA untagged and recognizable as "foreign," and targeted for destruction. Together, thesewould lead to higher rates of successful transduction.

If the infecting phage lacks some critical pieces of DNA necessary for replication, it is called: - incomplete. - defective. - mutated. - vegetative. - carcinogenic.

defective

If reasonably pure preparations of virus are available, the number of virus present may be determined by: - light microscopy. - photocolorimetry. - gas chromatography. - spectrophotometry. - electron microscopy.

electron microscopy.

You are graduating from nursing school in three months and have already lined up a new job. However, your employer informs you that before you start your job, it is mandatory for you to be vaccinated against hepatitis B, a double-stranded DNA virus that can cause the disease hepatitis. Your boyfriend, a biology major, wonders why you need to get the vaccine. You aced your microbiology class and you know a lot about both viruses and vaccines, so you understand why getting this vaccination is essential. You give your boyfriend a mini lesson on this by answering a few of his questions. Your boyfriend asks how animal viruses enter a host cell. You tell him that they can use one of two mechanisms: - fusion OR phagocytosis - budding OR fusion - endocytosis OR fusion - endocytosis OR budding - exocytosis OR fusion

endocytosis OR fusion

A dye often used for its ease and sensitivity to visualize nucleic acid after agarose gel electrophoresis is gold oxide. malachite green. nigrosin. ethidium bromide. crystal violet.

ethidium bromide.

the viral envelope resembles the

eukaryotic cell membrane

thymine dimer-containing section of DNA is cut out, resynthesized and sealed

excision repair

Convergent evolution

explains the morphological similarity yet major genetic differences found between slime molds and fungi AND refers to two different organisms that develop similar characteristics in adaptation to similar environments

Convergent evolution... 1. refers to two different organisms that develop similar characteristics in adaptation to similar environments 2.explains the morphological similarity yet major genetic differences found between slime molds and fungi AND refers to two different organisms that develop similar characteristics in adaptation to similar environments. 3. explains the morphological similarity yet major genetic differences found between slime molds and fungi.

explains the morphological similarity yet major genetic differences found between slime molds and fungi AND refers to two different organisms that develop similar characteristics in adaptation to similar environments.

The bacterial viruses that are released by a process termed extrusion are called: - filamentous phages. - lambda viruses. - temperate phages. - helical phages. - lysogenic viruses.

filamentous phages.

Azotobacter -is used as an indicator of fecal pollution. - forms endospores. - fixes carbon dioxide. -is a hyperthermophile. -fixes nitrogen.

fixes nitrogen - and forms cysts

Swarmer cells are

formed by sheathed bacteria.

In conjugation, transformation, or transduction, the recipient bacteria is most likely to accept donor DNA from any source. from any species of bacteria. from the same species of bacteria. only through plasmids. from any source AND only through plasmids.

from the same species of bacteria.

Sexual reproduction in algae involves meiosis that results in the production of: 1. spores with twice as much DNA as the parental cells. 2. gametes with the same amount of DNA as in the parental cells. 3. gametes with half the amount of DNA as in the parental cells. 4. swarming cells with the same amount of DNA as the parental cells. 5. spores with the same amount of DNA as the parental cells.

gametes with half the amount of DNA as in the parental cells.

Bacteria that have properties of both the donor and recipient cells are the result of UV light. SOS repair. frame shift mutations. genetic recombination.

genetic recombination

The term phototroph refers to an organism that

gets energy from sunlight

To increase the chance of detecting carcinogens in the Ames Test, the test substance is treated with penicillin. heat. ground up rat liver. reverse transcriptase. penicillin AND heat.

ground up rat liver

Prokaryotic cell mutations can be observed very quickly because the prokaryotic chromosome is diploid. polyploid. haploid. polysomal.

haploid

The 3' end of DNA has a hydroxyl group attached to the number 3 carbon of deoxyribose. attaches to the 3' phosphate group of the incoming nucleotide. always has thymine and uracil attached to it. has a hydroxyl group attached to the number 3 carbon of ribose. usually has guanine and guanine attached to it.

has a hydroxyl group attached to the number 3 carbon of deoxyribose.

The primer used in Sanger (dideoxy chain termination) sequencing has a nucleotide sequence complementary to the 3' end of the region to be copied. can have any random nucleotide sequence. must have a sequence beginning and ending with the same nucleotide. has a nucleotide sequence complementary to the 5' end of the region to be copied. has a nucleotide sequence complementary to the 5' end or the 3' end of the region to be copied.

has a nucleotide sequence complementary to the 3' end of the region to be copied.

The Ames test is useful as a rapid screen test to identify those compounds that

have a high probability of being carcinogenic

The best known chronic infection involves: - herpes. - hepatitis B. - chickenpox. - hepatitis A. - influenza.

hepatitis B

The best-known examples of viruses that cause latent infections are: - measles AND chickenpox. - polio AND herpes. - herpes AND measles. - herpes AND chickenpox. - chickenpox AND polio.

herpes AND chickenpox.

Disagreements between conclusions obtained from rDNA data and other techniques may be explained by

horizontal gene transfer

Chemical mutagens often act by altering the alkyl groups of the nucleobase. nucleobase sequence. number of binding sites on the nucleobase. hydrogen bonding properties of the nucleobase.

hydrogen bonding properties of the nucleobase.

The two strands of DNA are bonded to one another by hydrogen bonds. carbon bonds. disulfide bridges. oxygen bonds. covalent bonds.

hydrogen bonds.

Knowing the sequence of a genome is useful in identifying genetic alterations associated with disease, studying evolutionary relationships, AND determining protein sequences. studying evolutionary relationships AND determining protein sequences. identifying genetic alterations associated with disease AND studying evolutionary relationships. determining protein sequences BUT not identifying genetic changes. determining protein sequences AND identifying genetic alterations associated with disease.

identifying genetic alterations associated with disease, studying evolutionary relationships, AND determining protein sequences.

DNA repair mechanisms occur only in prokaryotes. only in eukaryotes. in both eukaryotes and prokaryotes. in neither eukaryotes or prokaryotes.

in both eukaryotes and prokaryotes.

Microorganisms can also be placed in ____________________ groups that are may be genetically unrelated.

informal ex) lactic acid bacteria, anoxygenic phototrophs, endospore formers, sulfate reducers

The clustered, regularly interspaced short palindromic repeats (CRISPR) system in bacterial cells has been called the "immune" system of bacteria. CRISPR protect bacteria from a repeat infection from the same phage because bacterial cells:

integrate fragments from the phage DNA in their own chromosomes and target for destruction any DNA that contains the same fragments in the future

Planar molecules used as chemical mutagens are called

intercalating agents

Planar molecules used as chemical mutagens are called nitrous oxide. base analogs. alkylating agents. intercalating agents.

intercalating agents

Sulfuric acid is

involved in bioleaching AND produced by unicellular sulfur-oxidizers.

The lac operon is an example of a regulon. is an example of constitutive control. is an example of positive control. produces lactose. is an example of negative control.

is an example of negative control.

Glucose is preferentially used over sucrose in E. coli as a result of catabolite repression AND levels are correlated with cAMP levels. is preferentially used over lactose in E. coli as a result of catabolite repression AND levels directly affect the production of lactose dehydrogenase. is preferentially used over lactose in E. coli as a result of catabolite repression AND levels are correlated with cAMP levels. is preferentially used over sucrose in E. coli as a result of catabolite repression AND levels are directly sensed via catabolite repression. is preferentially used over lactose in E. coli as a result of catabolite repression AND glucose levels are the inverse of cAMP levels.

is preferentially used over lactose in E. coli as a result of catabolite repression AND glucose levels are the inverse of cAMP levels.

Hydrogen sulfide: - has a strong citrus smell. - is produced when nitrate is used as terminal electron acceptor. - is produced by Desulfovibrio. - may react with iron to produce a deep red precipitate. - All of the answer choices are correct.

is produced by Desulfvibrio -has a strong rotten egg smell -is produced when sulfur compounds are used as terminal electron acceptors. - may react with iron to produce a black percipitate

The P-site is a promoter site on the ribosome. is found on the polymerase enzyme. is an allosteric site on an enzyme. is the peptidyl site on the ribosome. is an allosteric site AND is a promoter site.

is the peptidyl site on the ribosome.

All of the statements about specialized transduction are correct EXCEPT: - it involves temperate phages. - it involves the random transmission of any gene. - it involves the transfer of a few specific genes. - it involves a defective virus. - it only involves genes near the viral DNA integration site.

it involves the random transmission of any gene. - that is with generalized transduction

Which is true about the RNA transcript? - it is formed using the DNA minus strand as a template - it is formed using the DNA minus strand as a template, it has the same 5'-3' orientation as the DNA positive strand AND the template starts at the promoter region - it has the same 5'-3' orientation as the DNA positive strand - it is made in short fragments that are then stitched together - the template starts at the promoter region

it is formed using the DNA minus strand as a template, it has the same 5'-3' orientation as the DNA positive strand AND the template starts at the promoter region

mycoplasma

lack peptidoglycan, are the smallest free-living organisms AND have sterols in their membranes - mycoplasma has NO CELL WALL

Protozoan classification is based on their means of

locomotion

Prosthecae are an adaptation for

low nutrient aquatic environments - for attachment and nutrient absorption

The phenomenon responsible for the ability of Corynebacterium diphtherium to produce the virulent toxin responsible for the devastating effects of diphtheria is called: - self-assembly. - phase variation. - matrix conversion. - lysogenic conversion. - prion protein.

lysogenic converstion

Your niece has been diagnosed with Diamond-Blackfan anemia, an extremely rare disorder of the bone marrow that causes people have a low red blood cell (RBC) count. The disease is classified as a ribosomal protein disease, meaning that one or more of the genes involved in ribosome production is/are mutated, and the ribosomes are not synthesized properly. Although it is not currently understood why mutations in ribosome biosynthesis affect blood cell formation particularly, you are able to help your sister understand the role of ribosomes in the cell and the consequence of ribosome failure, so that she has a better grasp of her child's condition. Ribosomes are involved in generating proteins in a cell. The other components directly needed for this process to occur are DNA, DNA polymerase, and amino acids mRNA, tRNA, and nucleic acids a nucleolus, tRNA, and nucleic acids a nucleus, tRNA, and amino acids mRNA, tRNA, and amino acids

mRNA, tRNA, and amino acids

Nematodes: - includes the trematodes. - are carried by bacteria and fungi. - may enter the gastrointestinal tract or the blood. - only infect aquatic plants. - have flat, segmented bodies.

may enter the gastrointestinal tract or the blood.

Dimorphic fungi - may grow as mycelia or yeast AND are mushrooms. are strictly hyphae AND are often associated with disease in humans. - are often associated with disease in humans AND are mushrooms. - are strictly yeasts AND are often associated with disease in humans. - may grow as mycelia or yeast AND are often associated with disease in humans.

may grow as mycelia or yeast AND are often associated with disease in humans.

Carriers: - have been cured of the infection. - may have a persistent infection. - may be a source of infection. - may have a persistent infection AND may be a source of infection. - usually show symptoms of the disease AND may be a source of infection.

may have a persistent infection AND may be a source of infection.

The regulatory protein may inhibit or enhance transcription. binds to the operator region of RNA. binds to the promoter region of DNA. may control translation of the operon. affects the activity of the DNA polymerase.

may inhibit or enhance transcription.

Schizogony: 1. means multiple fissions AND is performed by protozoa. 2.is performed by protozoa AND is a type of reproduction. 3.is a form of reproduction AND means multiple fissions. 4.is performed by bacteria AND is performed by protozoa. 5.means multiple fissions AND is performed by bacteria.

means multiple fissions AND is performed by protozoa.

Outside of living cells, viruses are

metabolically inert

Archaea are typically found living in extreme environments. An exception to this are the: - methanogens. - sulfur-oxidizing archaea. - methanogens AND sulfur-reducing archaea. - sulfur-reducing archaea. - sulfur-oxidizing archaea AND sulfur-reducing archaea.

methanogens

multiple enzymes may repair an A-C error left unrecognized by DNA polymerase

mismatch repair

The most necessary habitat requirement of protozoa is: 1. Light 2. Moisture 3. UV light 4. basic pH 5. heat

moisture

The terms yeast, mold, and mushrooms refers to fungal

morphology

The terms yeast, mold, and mushrooms refers to: - fungal - morphology. - nutrition. - reproduction. - parasites. - staining.

morphology

Many spirochetes are difficult to cultivate, so their classification is based on their: - number of flagella AND morphology. - ability to cause disease AND pattern of flagella. - number of chromosomes AND pattern of flagella. - morphology AND ability to cause disease. - pattern of pili AND flexible cell wall.

morphology AND ability to cause disease.

The source of variation among microorganisms that were once identical is antibiotic resistance. virulence factors. sigma factors. mutation.

mutation

Fungal diseases are generally referred to as

mycoses

Fungal diseases are generally referred to as:

mycoses

Complex structures called fruiting bodies are a characteristic of: - Streptomyces. - myxobacteria. - lactic acid bacteria. - Clostridia. - bacilli.

myxobacteria.

Prions affect the: - respiratory system. - lymphatic system. - nervous system. - urogenital system. - gastrointestinal tract.

nervous system

Lactic acid bacteria such as Lactococcus

obligate fermentors

Using phages to treat a bacterial infection is an interesting idea because: - of the increasing problem of antibiotic resistance in pathogens. - lysed bacteria pose no threat to a person's health. - of the increasing problem of antibiotic resistance in people. - a single phage can be genetically engineered to infect many different species of bacteria. - a single type of phage can destroy a wide range of strains of the same pathogen.

of the increasing problem of antibiotic resistance in pathogens.

Algae: - are always saprophytic or parasitic. - are only found in the soil. - have a vascular system similar to that of plants. - often grow in areas where other forms of life may have difficulty. - are strictly macroscopic organisms.

often grow in areas where other forms of life may have difficulty.

Filamentous phages: - only infect E. coli lacking pili. - infect E. coli regardless of the presence of pili. - only infect E. coli that have pili. - do not infect E. coli. - only infect Gram-negative E. coli.

only infect E. coli that have pili.

Pediculus humanus

only uses humans as a host AND can transmit a bacterial disease

Pediculus humanus... 1. only uses humans as a host AND is carried by mosquitoes. 2. is an obligate intracellular parasite AND only uses humans as a host. 3. can transmit a bacterial disease AND only infects feet. 4. only uses humans as a host AND can transmit a bacterial disease. 5. only infects feet AND can transmit a bacterial disease.

only uses humans as a host AND can transmit a bacterial disease.

The DNA site to which the repressor protein binds is the operator. operon. regulon. repressor. Starter.

operator.

The set of genes in bacteria that are linked together and transcribed as a single unit is referred to as a(n) operon. operator. promoter. regulon. Repressor.

operon.

One group of animal viruses that are able to agglutinate red blood cells are the

orthomyxoviruses.

Clostridium, Lactobacillus, and Propionibacterium all: - oxidize inorganic compounds AND use organic compounds as terminal electron acceptors. - neutralize organic compounds AND use organic compounds as terminal electron acceptors. - oxidize organic compounds AND use organic compounds as terminal electron acceptors. - oxidize inorganic compounds AND use sulfur compounds as terminal electron acceptors. - oxidize organic compounds AND use sulfur compounds as terminal electron acceptors.

oxidize organic compounds AND use organic compounds as terminal electron acceptors.

Comparatively greater energy is released when: - carbon dioxide is the final electron acceptor. - oxygen is the final electron acceptor. - fermentation occurs. - nitrate is the final electron acceptor. - hydrogen is the final electron acceptor.

oxygen is the final electron acceptor.

To increase the proportion of mutants in a population of bacteria one may use direct selection. replica plating. penicillin enrichment. individual transfer.

penicillin enrichment

To increase the proportion of mutants in a population of bacteria one may use - direct selection. - replica plating. - penicillin enrichment. - individual transfer.

penicillin enrichment.

The characteristics displayed by an organism in any given environment is its genotype. archaetype. mutatotype. phenotype.

phenotype

The properties of a cell which are determined by its DNA composition are its phenotype. genotype. metabolism. nucleoid.

phenotype

Non-constituitive system with visible light energy breaking covalent T-T bonds

photoreactivation

Thymine dimers are dealt with by

photoreactivation repair AND excision repair.

Thymine dimers are dealt with by no repair mechanisms. photoreactivation repair. SOS repair. excision repair. photoreactivation repair AND excision repair.

photoreactivation repair AND excision repair.

Free-floating, photosynthetic organisms found in marine environments are blue-green algae. phytoplankton. omega-3s Bucella. krill.

phytoplankton

Spongiform encephalopathy occurs in all of the following EXCEPT - humans. - plants. - sheep. - cattle. - cattle AND sheep.

plants

A common vector used for cloning genes is/are

plasmids

A difference between plasmids and fragments of DNA that have been transferred between cells is:

plasmids can replicate independently.

Bdellovibrio species: - are parasites of plants. - are filamentous. - may fix nitrogen. - prey on other bacteria. - are photosynthetic.

prey on other bacteria.

A common way to identify the E. coli that carries the desired recombinant DNA is by using a - vector. - probe. - host. - plasmid.

probe

A common way to identify the E. coli that carries the desired recombinant DNA is by using a(n) probe. antibiotic. vector. host. Plasmid.

probe.

Gonyaulax... 1. infects the nervous system of humans AND is a monoflagellate. 2. produces a non-protein enterotoxin AND is a dinoflagellate. 3. produces a protein neurotoxin AND is a dinoflagellate. 4. is a monoflagellate AND produces a non-protein neurotoxin. 5. produces a non-protein neurotoxin AND is a dinoflagellate.

produces a non-protein neurotoxin AND is a dinoflagellate.

Propionibacterium: - produces propionic acid AND is responsible for the holes in Swiss cheese. - is responsible for the holes in Swiss cheese AND requires aerobic environments. - produces propionic acid AND requires aerobic environments. - produces lactic acid AND is a Gram-negative organism. - produces lactic acid AND is responsible for the holes in Swiss cheese.

produces propionic acid AND is responsible for the holes in Swiss cheese.

The specific sequence of nucleotides in the DNA to which the RNA polymerase binds is the

promoter region

The specific sequence of nucleotides in the DNA to which the RNA polymerase binds is the regulatory region. starter region. core region. sigma region. promoter region.

promoter region.

Your patient has a fever of 39 oC, sore throat, cough, and chest pain. You ask her whether she has had pneumococcal vaccine this year, which protects against the the 23 most common strains of the causative bacterium Streptococcus pneumoniae. She says she has not. Your patient has a number of questions that you answer to help her understand the genetics of the organism causing her illness. You explain that transcription starts at a particular region on the DNA template called the ________, and ends at a sequence called the ________. promoter; stop codon initiator; terminator start codon; terminator start codon; stop codon promoter; terminator

promoter; terminator

Transcription begins at the ________ and ends at the ________, while translation begins at the ________ and ends at the ________. start codon; stop codon; promoter; terminator initiator; ender; starter; stopper promoter; stop codon; terminator; stop codon promoter; terminator; start codon; stop codon promoter; start codon; terminator; stop codon

promoter; terminator; start codon; stop codon

Propionibacterium produces

propionic acid

Single-celled eukaryotic organisms that lack chlorophyll are called

protozoa

The ability to exist as either a trophozoite or a cyst is characteristic of many: - bacteria. - archaea. - protozoa. - fungi. - viruses.

protozoa

Single-celled eukaryotic organisms that lack chlorophyll include: - yeasts AND cyanobacteria. - algae AND yeasts. - protozoa AND yeasts. - protozoa AND cyanobacteria. - algae AND archaea.

protozoa AND yeasts.

Antibiotics cause mutations to occur. may act as alkylating mutagens. provide an environment in which pre-existing mutants survive. increase the rate of spontaneous mutation.

provide an environment in which pre-existing mutants survive.

During attachment of phage to E. coli, the phage: - randomly bumps into the bacteria AND attaches to proteins or carbohydrates on the bacterial surface. - actively seeks out the bacteria AND attaches to proteins or carbohydrates on the bacterial surface. - actively seeks out the bacteria AND attaches to the bacterial DNA. - randomly bumps into the bacteria AND attaches to the bacterial DNA. - randomly bumps into the bacteria AND attaches to the bacterial RNA.

randomly bumps into the bacteria AND attaches to proteins or carbohydrates on the bacterial surface.

DNA molecules that contain pieces of DNA from two different sources are defined as gene cloning. mutation. biotechnology. genetic engineering. recombinant DNA.

recombinant DNA.

Operon(s) in bacteria refers to a group of genes that are controlled in a coordinated manner AND involve polycistronic DNA. refers to a group of genes that are controlled in a coordinated manner AND involve monocistronic mRNA. refers to a group of genes that are controlled in a coordinated manner AND involve monocistronic DNA. refers to a group of genes that are controlled in a coordinated manner AND involve polycistronic mRNA. refers to a group of genes that are controlled in a coordinated manner AND involve both monocistronic and polycistronic DNA.

refers to a group of genes that are controlled in a coordinated manner AND involve polycistronic mRNA.

Operons in bacteria

refers to a group of genes that are coordinately controlled AND involve polycistronic mRNA.

Viruses acquire envelopes around their nucleocapsids during

release

A clever technique that streamlines the identification of auxotrophic mutants is gas chromatography. replica plating. direct selection. reversion.

replica plating

Streptomyces

resemble fungi in their pattern of growth AND produce a number of antibiotics.

The transcription terminator adds a terminator nucleotide to the RNA, AND results in a hairpin loop structure in RNA. results in a hairpin loop structure in RNA, AND stops DNA polymerase. stops DNA polymerase, AND results in the polymerase falling off the DNA template. results in a hairpin loop structure in RNA, AND results in the polymerase falling off the DNA template. stops DNA polymerase, AND adds a terminator nucleotide to the RNA.

results in a hairpin loop structure in RNA, AND results in the polymerase falling off the DNA template.

DNA replication is interspersive. configurative. semiconservative. conservative. Redundant.

semiconservative.

The agarose used in electrophoresis denatures DNA/RNA. selectively sorts recombinant DNA from host DNA. separates DNA fragments by size. chemically binds to the DNA. interacts electrically with the DNA.

separates DNA fragments by size.

Bacteria use ______ attached to the polymerase and they direct RNA polymerase to promoters; eukaryotic cells use ______ that instead attach directly to the DNA first.

sigma factors; transcription factors

Bacteria use ________ attached to the polymerase to direct RNA polymerase to promoters; eukaryotic cells use ________ that attach directly to the DNA first instead. ribosomes; sigma factors tRNA; rRNA sigma factors; tRNA transcription factors; sigma factors sigma factors; transcription factors

sigma factors; transcription factors

what structure is indicated by: 10A, 15T, 3G, 7C?

single stranded DNA

The filamentous phages all contain: - single-stranded RNA. - single-stranded DNA. - single-stranded RNA, OR single-stranded DNA - double-stranded RNA. - double-stranded DNA.

single-stranded DNA.

Agarose gel electrophoresis separates nucleic acid fragments according to shape. nucleobase sequence. size. type of 5C sugar. Density.

size.

When cellular slime molds run out of food, they form a: 1. bladder. 2. rhizoid. 3. myxamoeba. 4. plasmodium. 5. slug.

slug

Treponema and Borrelia are

spirochetes

Endoflagella (axial filaments) are only found on: Movement of spirochetes occurs by means of structures called:

spirochetes -use for locomotion -axial filaments

The science that studies organisms to arrange them into groups, or _________, is:

taxa, Taxonomy

Phages that can either replicate and cause cell lysis or can integrate their DNA into the host DNA are called

temperate phages

The lactobacilli, in their role as normal flora of the vagina, help the vagina resist infection by contributing to

the acidity of the vagina

When E. coli is grown in medium containing both glucose and lactose, the cells grow fastest initially when glucose is available. the cells use lactose first, then glucose. the cells use the glucose and then stop growing. the cells grow at the same rate until all sugars are depleted. the cells growth fastest after lactose is used up.

the cells grow fastest initially when glucose is available.

post-translational modification may include

the folding of the protein, often with the aid of chaperones AND removal of the signal sequence.

The designation his- refers to the genotype of a bacterium that lacks a functional gene for histidine synthesis. the genotype of a bacterium that has a functional gene for histidine synthesis. the opposite of a hers gene. bacteria that are auxotrophic for histidine. the genotype of a bacterium that lacks a functional gene for histidine synthesis AND bacteria that are auxotrophic for histidine.

the genotype of a bacterium that lacks a functional gene for histidine synthesis AND bacteria that are auxotrophic for histidine.

The size of the amplified DNA fragment generated during PCR is determined by the location to which the primers anneal. how many cycles are performed. how much Taq polymerase is used. the size of the template DNA. the time for each cycle.

the location to which the primers anneal.

The size of the amplified DNA fragment generated during PCR is determined by

the locations to which the primers anneal

The diploid character of eukaryotic cells may mask the appearance of a mutation since this may be a frame shift. the mutation is often reversible. the mutation may be palindromic. the matching chromosome may carry the dominant gene.

the matching chromosome may carry the dominant gene.

Direct selection involves inoculating cells onto growth media on which the mutant but not the parental cell type will grow. the mutation will be reversed. the nutrients necessary for mutation to occur are present. the mutagen is present.

the mutant but not the parental cell type will grow.

Direct selection involves inoculating cells onto growth media upon which

the mutant, but not the parental cell type, will grow

A danger in using E. coli in cloning is that working with E. coli requires a BSL3 laboratory. E. coli could cause disease. the outer membrane is toxic to humans. the human cells may reject the insertion. the exons may invert the introns.

the outer membrane is toxic to humans.

The integration of phage DNA into the bacterial chromosome occurs because of: - the similarity in enzyme metabolism in the phage and the bacterial cell. - the phage's ability to synthesize enzymes to enter the bacterium AND similar RNA nucleotides in both. - the phage's ability to synthesize an enzyme that integrates its DNA into the host's chromosome. - similarity in RNA nucleotides in both the phage and the bacterial host. - the phage's ability to synthesize enzymes that allow it to enter the bacterium.

the phage's ability to synthesize an enzyme that integrates its DNA into the host's chromosome. - the enzyme integrase

The lagging strand is necessary due to

the properties of the enzymes and the antiparallel nature of DNA.

The F plasmid carries the information for antibiotic resistance. recipient cell DNA replication. the Y chromosome. the sex pilus. antibiotic resistance AND the Y chromosome.

the sex pills

In E. coli 0157:H7 the 0157:H7 refers to the

the specific LPS and flagella type present

During penetration of E. coli by the T4 phage,: - the tail acts as a "hypodermic needle," injecting the phage DNA into the cell. - the protein fibers digest a hole in the cell wall. - the intact phage enters the host by endocytosis. - lysozyme is used to allow entry of the phage capsid. - the bacterial receptor molecules open a hole through the cell wall.

the tail acts as a "hypodermic needle," injecting the phage DNA into the cell.

Restriction enzymes have proved so useful in manipulating DNA because they protect eukaryotes against virus attack AND the sticky ends make it very easy to allow recombination of DNA with RNA. they cut at random sites AND the sticky ends make it very easy to allow recombination of any type of DNA. they cut at defined sites AND the sticky ends make it very easy to allow recombination of DNA with RNA. they protect eukaryotes against virus attack AND they cut both RNA and DNA. they cut at defined sites AND the sticky ends make it very easy to allow recombination of any type of DNA.

they cut at defined sites AND the sticky ends make it very easy to allow recombination of any type of DNA.

If the G+C content of two organisms is 45% in both

they may or may not be related

Irradiation of cells with ultraviolet light may cause 4 nucleotides to covalently bind together. thymine dimers. adenine complementary base pairing with cytosine. the addition of uracil.

thymine dimers

Lyme disease is transmitted by

ticks

Strain differences are helpful in

tracing the source of outbreaks of disease.

Your patient has a fever of 39 oC, sore throat, cough, and chest pain. You ask her whether she has had pneumococcal vaccine this year, which protects against the 23 most common strains of the causative bacterium Streptococcus pneumoniae. She says she has not. Your patient has a number of questions that you answer to help her understand the genetics of the organism causing her illness. You give your patient some general information on gene expression in cells. You explain that when cells divide, two processes are involved: replication and gene expression. Gene expression includes two related events: (i) copying the information encoded in DNA into RNA, a process called ________, followed by (ii) the interpretation of the information carried by the RNA to synthesize the encoded protein in a process called ________. binary fission; transcription translation, transcription transcription; translation replication; transcription replication; translation

transcription; translation

The mechanism by which genes are transferred into bacteria via viruses is called ellipsis. replica plating. transformation. transduction. conjugation.

transduction

Segments of DNA capable of moving from one area in the DNA to another are called base analogs. intercalating agents. transposons. palindromic sequences.

transposons

In order to get around the lack of ability of prokaryotes to remove introns from precursor RNA, it may be necessary to

turn mRNA into cDNA

Anoxygenic phototrophs: - use water as a source of electrons. - use the same form of chlorophyll found in terrestrial plants. - produce oxygen. - produce oxygen AND use the same form of chlorophyll found in terrestrial plants. - use hydrogen sulfide or organic compounds as a source of electrons.

use hydrogen sulfide or organic compounds as a source of electrons.

Fluorescence in situ hybridization (FISH) uses a labeled probe, is useful in microbial ecology, AND allows identification of particular bacterial groups in mixed samples. is useful in microbial ecology, allows identification of particular bacterial groups in mixed samples AND depends on electron microscopy. uses virus hosts, uses a labeled probe, AND is useful in microbial ecology. is useful in microbial ecology, allows identification of particular bacterial groups in mixed samples AND uses virus hosts. uses a labeled probe, allows identification of particular bacterial groups in mixed samples, AND uses virus hosts.

uses a labeled probe, is useful in microbial ecology, AND allows identification of particular bacterial groups in mixed samples.

A phage that replicates inside the host cell and then lyses its host during its release is a: - dormant phage. - temperate phage. - virulent or lytic phage. - lysogenic phage. - latent phage.

virulent or lytic phage. - ex) T4 lytic phage

Common vectors used for cloning genes are nucleotides. bacteria. plasmids. viruses. viruses AND plasmids.

viruses AND plasmids.

Woese was involved in determining rRNA sequences AND proposed breaking prokaryotes into two groups. was involved in determining DNA sequences AND proposed breaking eukaryotes into domains Archaea and Bacteria. was involved in determining rRNA sequences AND proposed breaking eukaryotes into domains Archaea and Bacteria. proposed breaking prokaryotes into two groups AND was involved in refining the Gram stain for classification purposes. proposed breaking eukaryotes into domains Archaea and Bacteria AND was involved in refining the Gram stain for classification purposes.

was involved in determining rRNA sequences AND proposed breaking prokaryotes into two groups.

From Ch 1 - The work of Tyndall and Cohn:

was used to explain why others investigating spontaneous generation had obtained results that were opposite of those obtained by Pasteur

You and your exercise buddy decide to go to Yosemite National Park to hike the famous El Capitan trail. You book your trip through a well known agency but before you leave for your vacation, you learn that there have been two cases of plague reported in people who recently visited a different area of the park. Your friend is anxious and tells you he thinks that plague is really dangerous and kills people everyone who gets it. He points out that this disease killed a lot of people during the Middle Ages, and says he doesn't want to do the trip after all. You decide to do some research on the plague and its causative agent before making a decision about your trip. Which of the following is NOT a vector? - Fly - Water - Tick - Mosquito - Flea

water

Plant pathology grew in importance as a field of study after it was shown that the Irish potato blight was caused by: - viruses. - bacteria. - water molds. - fungi. - amoeboid protozoa.

water mold

In the late nineteenth century, immigration from Ireland to the United States occurred in high numbers due to an infection of potatoes by:

water molds

When a vector that uses the lacZ gene as a second marker is used in a cloning experiment, bacteria that contain the recombinant DNA will give rise to white colonies. red colonies. cream colonies. blue colonies. All of the answer choices are correct.

white colonies.

Fungi capable of dimorphism grow either as: - yeast-like or mycelium. - rhizoids or hyphae. - spores or mushrooms. - germ tubes or buds. - yeast-like or mushrooms.

yeast-like or mycellium

A student complains that it makes no sense to worry about coliform bacteria in water, since we naturally possess harmless coliforms in our intestines anyway. Why do regulatory agencies worry about coliform bacteria in water supplies, then?

−Not all coliforms are harmless and symbiotic with human beings. Some may carry genes/proteins that can make them dangerous to humans. It's best to keep coliforms OUT of our drinking water, since it's difficult to identify which ones might be harmless and which ones might be harmful.